OBD-II PIDs

Template:Short description Template:Multiple issues OBD-II PIDs (On-board diagnostics Parameter IDs) are codes used to request data from a vehicle, used as a diagnostic tool.

SAE standard J1979 defines many OBD-II PIDs. All on-road vehicles and trucks sold in North America are required to support a subset of these codes, primarily for state mandated emissions inspections. Manufacturers also define additional PIDs specific to their vehicles. Though not mandated, many motorcycles also support OBD-II PIDs.

In 1996, light duty vehicles (less than Template:Convert) were the first to be mandated followed by medium duty vehicles (Template:Convert) in 2005. They are both required to be accessed through a standardized data link connector defined by SAE J1962.

Heavy duty vehicles (greater than Template:Convert) made after 2010, for sale in the US are allowed to support OBD-II diagnostics through SAE standard J1939-13 (a round diagnostic connector) according to CARB in title 13 CCR 1971.1. Some heavy duty trucks in North America use the SAE J1962 OBD-II diagnostic connector that is common with passenger cars, notably Mack and Volvo Trucks, however they use 29 bit CAN identifiers (unlike 11 bit headers used by passenger cars).

Services / Modes

There are 10 diagnostic services described in the latest OBD-II standard SAE J1979. Before 2002, J1979 referred to these services as "modes". They are as follows:

Service / Mode (hex)	Description
[[#Service 01|Template:Mono]]	Show current data
[[#Service 02|Template:Mono]]	Show freeze frame data
[[#Service 03|Template:Mono]]	Show stored Diagnostic Trouble Codes
[[#Service 04|Template:Mono]]	Clear Diagnostic Trouble Codes and stored values
[[#Service 05|Template:Mono]]	Test results, oxygen sensor monitoring (non CAN only)
Template:Mono	Test results, other component/system monitoring (Test results, oxygen sensor monitoring for CAN only)
Template:Mono	Show pending Diagnostic Trouble Codes (detected during current or last driving cycle)
Template:Mono	Control operation of on-board component/system
[[#Service 09|Template:Mono]]	Request vehicle information
Template:Mono	Permanent Diagnostic Trouble Codes (DTCs) (Cleared DTCs)

Vehicle manufacturers are not required to support all services. Each manufacturer may define additional services above #9 (e.g.: service 22 as defined by SAE J2190 for Ford/GM, service 21 for Toyota) for other information e.g. the voltage of the traction battery in a hybrid electric vehicle (HEV).

The nonOBD UDS services start at 0x10 to avoid overlap of ID-range.

Standard PIDs

The table below shows the standard OBD-II PIDs as defined by SAE J1979. The expected response for each PID is given, along with information on how to translate the response into meaningful data. Again, not all vehicles will support all PIDs and there can be manufacturer-defined custom PIDs that are not defined in the OBD-II standard.

Note that services 01 and 02 are basically identical, except that service 01 provides current information, whereas service 02 provides a snapshot of the same data taken at the point when the last diagnostic trouble code was set. The exceptions are PID 01, which is only available in service 01, and PID 02, which is only available in service 02. If service 02 PID 02 returns zero, then there is no snapshot and all other service 02 data is meaningless.

When using Bit-Encoded-Notation, quantities like C4 means bit 4 from data byte C. Each bit is numbered from 0 to 7, so 7 is the most significant bit and 0 is the least significant bit (See below).

A

B

C

D

A7

A6

A5

A4

A3

A2

A1

A0

B7

B6

B5

B4

B3

B2

B1

B0

C7

C6

C5

C4

C3

C2

C1

C0

D7

D6

D5

D4

D3

D2

D1

D0

Service Template:Mono - Show current data

PIDs (hex)	PID (Dec)	Data bytes returned	Description	Min value	Max value	Units	FormulaTemplate:Efn
Template:Mono	Template:Mono	4	PIDs supported [$01 - $20]				Bit encoded [A7..D0] == [PID $01..PID $20] See below
Template:Mono	Template:Mono	4	Monitor status since DTCs cleared. (Includes malfunction indicator lamp (MIL), status and number of DTCs, components tests, DTC readiness checks)				Bit encoded. See below
Template:Mono	Template:Mono	2	DTC that caused freeze frame to be stored.				Decoded as in service 3
Template:Mono	Template:Mono	2	Fuel system status				Bit encoded. See below
Template:Mono	Template:Mono	1	Calculated engine load	0	100	%	$\frac{100}{255}A$ (or $\frac{A}{2.55}$)
Template:Mono	Template:Mono	1	Engine coolant temperature	-40	215	°C	$A-40$
Template:Mono	Template:Mono	1	Short term fuel trim (STFT)—Bank 1	-100 (Reduce Fuel: Too Rich)	99.2 (Add Fuel: Too Lean)	%	$$\frac{100}{128}A-100$$(or $\frac{A}{1.28}-100$ )
Template:Mono	Template:Mono	1	Long term fuel trim (LTFT)—Bank 1
Template:Mono	Template:Mono	1	Short term fuel trim (STFT)—Bank 2
Template:Mono	Template:Mono	1	Long term fuel trim (LTFT)—Bank 2
Template:Mono	Template:Mono	1	Fuel pressure (gauge pressure)	0	765	kPa	$3A$
Template:Mono	Template:Mono	1	Intake manifold absolute pressure	0	255	kPa	$A$
Template:Mono	Template:Mono	2	Engine speed	0	16,383.75	rpm	$\frac{256A+B}{4}$
Template:Mono	Template:Mono	1	Vehicle speed	0	255	km/h	$A$
Template:Mono	Template:Mono	1	Timing advance	-64	63.5	° before TDC	$\frac{A}{2}-64$
Template:Mono	Template:Mono	1	Intake air temperature	-40	215	°C	$A-40$
Template:Mono	Template:Mono	2	Mass air flow sensor (MAF) air flow rate	0	655.35	g/s	$\frac{256A+B}{100}$
Template:Mono	Template:Mono	1	Throttle position	0	100	%	$\frac{100}{255}A$
Template:Mono	Template:Mono	1	Commanded secondary air status				Bit encoded. See below
Template:Mono	Template:Mono	1	Oxygen sensors present (in 2 banks)				[A0..A3] == Bank 1, Sensors 1-4. [A4..A7] == Bank 2...
Template:Mono	Template:Mono	2	Oxygen Sensor 1 A: Voltage B: Short term fuel trim	0 -100	1.275 99.2	V %	$$\frac{A}{200}$$$$\frac{100}{128}B-100$$(if B==$FF, sensor is not used in trim calculation)
Template:Mono	Template:Mono	2	Oxygen Sensor 2 A: Voltage B: Short term fuel trim
Template:Mono	Template:Mono	2	Oxygen Sensor 3 A: Voltage B: Short term fuel trim
Template:Mono	Template:Mono	2	Oxygen Sensor 4 A: Voltage B: Short term fuel trim
Template:Mono	Template:Mono	2	Oxygen Sensor 5 A: Voltage B: Short term fuel trim
Template:Mono	Template:Mono	2	Oxygen Sensor 6 A: Voltage B: Short term fuel trim
Template:Mono	Template:Mono	2	Oxygen Sensor 7 A: Voltage B: Short term fuel trim
Template:Mono	Template:Mono	2	Oxygen Sensor 8 A: Voltage B: Short term fuel trim
Template:Mono	Template:Mono	1	OBD standards this vehicle conforms to	1	250		enumerated. See below
Template:Mono	Template:Mono	1	Oxygen sensors present (in 4 banks)				Similar to PID $13, but [A0..A7] == [B1S1, B1S2, B2S1, B2S2, B3S1, B3S2, B4S1, B4S2]
Template:Mono	Template:Mono	1	Auxiliary input status				A0 == Power Take Off (PTO) status (1 == active) [A1..A7] not used
Template:Mono	Template:Mono	2	Run time since engine start	0	65,535	s	$256A+B$
Template:Mono	Template:Mono	4	PIDs supported [$21 - $40]				Bit encoded [A7..D0] == [PID $21..PID $40] See below
Template:Mono	Template:Mono	2	Distance traveled with malfunction indicator lamp (MIL) on	0	65,535	km	$256A+B$
Template:Mono	Template:Mono	2	Fuel Rail Pressure (relative to manifold vacuum)	0	5177.265	kPa	$0.079(256A+B)$
Template:Mono	Template:Mono	2	Fuel Rail Gauge Pressure (diesel, or gasoline direct injection)	0	655,350	kPa	$10(256A+B)$
Template:Mono	Template:Mono	4	Oxygen Sensor 1 AB: Air-Fuel Equivalence Ratio (lambda,λ) CD: Voltage	0 0	< 2 < 8	ratio V	$$\frac{2}{65536}(256A+B)$$$$\frac{8}{65536}(256C+D)$$
Template:Mono	Template:Mono	4	Oxygen Sensor 2 AB: Air-Fuel Equivalence Ratio (lambda,λ) CD: Voltage
Template:Mono	Template:Mono	4	Oxygen Sensor 3 AB: Air-Fuel Equivalence Ratio (lambda,λ) CD: Voltage
Template:Mono	Template:Mono	4	Oxygen Sensor 4 AB: Air-Fuel Equivalence Ratio (lambda,λ) CD: Voltage
Template:Mono	Template:Mono	4	Oxygen Sensor 5 AB: Air-Fuel Equivalence Ratio (lambda,λ) CD: Voltage
Template:Mono	Template:Mono	4	Oxygen Sensor 6 AB: Air-Fuel Equivalence Ratio (lambda,λ) CD: Voltage
Template:Mono	Template:Mono	4	Oxygen Sensor 7 AB: Air-Fuel Equivalence Ratio (lambda,λ) CD: Voltage
Template:Mono	Template:Mono	4	Oxygen Sensor 8 AB: Air-Fuel Equivalence Ratio (lambda,λ) CD: Voltage
Template:Mono	Template:Mono	1	Commanded EGR	0	100	%	$\frac{100}{255}A$
Template:Mono	Template:Mono	1	EGR Error	-100	99.2	%	$\frac{100}{128}A-100$
Template:Mono	Template:Mono	1	Commanded evaporative purge	0	100	%	$\frac{100}{255}A$
Template:Mono	Template:Mono	1	Fuel Tank Level Input	0	100	%	$\frac{100}{255}A$
Template:Mono	Template:Mono	1	Warm-ups since codes cleared	0	255		$A$
Template:Mono	Template:Mono	2	Distance traveled since codes cleared	0	65,535	km	$256A+B$
Template:Mono	Template:Mono	2	Evap. System Vapor Pressure	-8,192	8191.75	Pa	$\frac{256A+B}{4}$ (AB is two's complement signed)
Template:Mono	Template:Mono	1	Absolute Barometric Pressure	0	255	kPa	$A$
Template:Mono	Template:Mono	4	Oxygen Sensor 1 AB: Air-Fuel Equivalence Ratio (lambda,λ) CD: Current	0 -128	< 2 <128	ratio mA	$$\frac{2}{65536}(256A+B)$$$$\frac{256C+D}{256}-128$$
Template:Mono	Template:Mono	4	Oxygen Sensor 2 AB: Air-Fuel Equivalence Ratio (lambda,λ) CD: Current
Template:Mono	Template:Mono	4	Oxygen Sensor 3 AB: Air-Fuel Equivalence Ratio (lambda,λ) CD: Current
Template:Mono	Template:Mono	4	Oxygen Sensor 4 AB: Air-Fuel Equivalence Ratio (lambda,λ) CD: Current
Template:Mono	Template:Mono	4	Oxygen Sensor 5 AB: Air-Fuel Equivalence Ratio (lambda,λ) CD: Current
Template:Mono	Template:Mono	4	Oxygen Sensor 6 AB: Air-Fuel Equivalence Ratio (lambda,λ) CD: Current
Template:Mono	Template:Mono	4	Oxygen Sensor 7 AB: Air-Fuel Equivalence Ratio (lambda,λ) CD: Current
Template:Mono	Template:Mono	4	Oxygen Sensor 8 AB: Air-Fuel Equivalence Ratio (lambda,λ) CD: Current
Template:Mono	Template:Mono	2	Catalyst Temperature: Bank 1, Sensor 1	-40	6,513.5	°C	$\frac{256A+B}{10}-40$
Template:Mono	Template:Mono	2	Catalyst Temperature: Bank 2, Sensor 1
Template:Mono	Template:Mono	2	Catalyst Temperature: Bank 1, Sensor 2
Template:Mono	Template:Mono	2	Catalyst Temperature: Bank 2, Sensor 2
Template:Mono	Template:Mono	4	PIDs supported [$41 - $60]				Bit encoded [A7..D0] == [PID $41..PID $60] See below
Template:Mono	Template:Mono	4	Monitor status this drive cycle				Bit encoded. See below
Template:Mono	Template:Mono	2	Control module voltage	0	65.535	V	$\frac{256A+B}{1000}$
Template:Mono	Template:Mono	2	Absolute load value	0	25,700	%	$\frac{100}{255}(256A+B)$
Template:Mono	Template:Mono	2	Commanded Air-Fuel Equivalence Ratio (lambda,λ)	0	< 2	ratio	$\frac{2}{65536}(256A+B)$
Template:Mono	Template:Mono	1	Relative throttle position	0	100	%	$\frac{100}{255}A$
Template:Mono	Template:Mono	1	Ambient air temperature	-40	215	°C	$A-40$
Template:Mono	Template:Mono	1	Absolute throttle position B	0	100	%	$\frac{100}{255}A$
Template:Mono	Template:Mono	1	Absolute throttle position C
Template:Mono	Template:Mono	1	Accelerator pedal position D
Template:Mono	Template:Mono	1	Accelerator pedal position E
Template:Mono	Template:Mono	1	Accelerator pedal position F
Template:Mono	Template:Mono	1	Commanded throttle actuator
Template:Mono	Template:Mono	2	Time run with MIL on	0	65,535	min	$256A+B$
Template:Mono	Template:Mono	2	Time since trouble codes cleared
Template:Mono	Template:Mono	4	Maximum value for Fuel–Air equivalence ratio, oxygen sensor voltage, oxygen sensor current, and intake manifold absolute pressure	0, 0, 0, 0	255, 255, 255, 2550	ratio, V, mA, kPa	$A$, $B$, $C$, $D\times 10$
Template:Mono	Template:Mono	4	Maximum value for air flow rate from mass air flow sensor	0	2550	g/s	$A\times 10$; $B$, $C$, and $D$ are reserved for future use
Template:Mono	Template:Mono	1	Fuel Type				From fuel type table see below
Template:Mono	Template:Mono	1	Ethanol fuel %	0	100	%	$\frac{100}{255}A$
Template:Mono	Template:Mono	2	Absolute Evap system Vapor Pressure	0	327.675	kPa	$\frac{256A+B}{200}$
Template:Mono	Template:Mono	2	Evap system vapor pressure	-32,768	32,767	Pa	$256A+B$(AB is two's complement signed)
Template:Mono	Template:Mono	2	Short term secondary oxygen sensor trim, A: bank 1, B: bank 3	-100	99.2	%	$\frac{100}{128}A-100$ $\frac{100}{128}B-100$
Template:Mono	Template:Mono	2	Long term secondary oxygen sensor trim, A: bank 1, B: bank 3
Template:Mono	Template:Mono	2	Short term secondary oxygen sensor trim, A: bank 2, B: bank 4
Template:Mono	Template:Mono	2	Long term secondary oxygen sensor trim, A: bank 2, B: bank 4
Template:Mono	Template:Mono	2	Fuel rail absolute pressure	0	655,350	kPa	$10(256A+B)$
Template:Mono	Template:Mono	1	Relative accelerator pedal position	0	100	%	$\frac{100}{255}A$
Template:Mono	Template:Mono	1	Hybrid battery pack remaining life	0	100	%	$\frac{100}{255}A$
Template:Mono	Template:Mono	1	Engine oil temperature	-40	210	°C	$A-40$
Template:Mono	Template:Mono	2	Fuel injection timing	-210.00	301.992	°	$\frac{256A+B}{128}-210$
Template:Mono	Template:Mono	2	Engine fuel rate	0	3212.75	L/h	$\frac{256A+B}{20}$
Template:Mono	Template:Mono	1	Emission requirements to which vehicle is designed				Bit Encoded
Template:Mono	Template:Mono	4	PIDs supported [$61 - $80]				Bit encoded [A7..D0] == [PID $61..PID $80] See below
Template:Mono	Template:Mono	1	Driver's demand engine - percent torque	-125	130	%	$A-125$
Template:Mono	Template:Mono	1	Actual engine - percent torque	-125	130	%	$A-125$
Template:Mono	Template:Mono	2	Engine reference torque	0	65,535	N⋅m	$256A+B$
Template:Mono	Template:Mono	5	Engine percent torque data	-125	130	%	$A-125$ Idle $B-125$ Engine point 1 $C-125$ Engine point 2 $D-125$ Engine point 3 $E-125$ Engine point 4
Template:Mono	Template:Mono	2	Auxiliary input / output supported				Bit Encoded
Template:Mono	Template:Mono	5	Mass air flow sensor	0	2047.96875	g/s	[A0]== Sensor A Supported [A1]== Sensor B Supported Sensor A:$\frac{256B+C}{32}$ Sensor B:$\frac{256D+E}{32}$
Template:Mono	Template:Mono	3	Engine coolant temperature	-40	215	°C	[A0]== Sensor 1 Supported [A1]== Sensor 2 Supported Sensor 1:$B-40$ Sensor 2:$C-40$
Template:Mono	Template:Mono	3	Intake air temperature sensor	-40	215	°C	[A0]== Sensor 1 Supported [A1]== Sensor 2 Supported Sensor 1:$B-40$ Sensor 2:$C-40$
Template:Mono	Template:Mono	7	Actual EGR, Commanded EGR, and EGR Error
Template:Mono	Template:Mono	5	Commanded Diesel intake air flow control and relative intake air flow position
Template:Mono	Template:Mono	5	Exhaust gas recirculation temperature
Template:Mono	Template:Mono	5	Commanded throttle actuator control and relative throttle position
Template:Mono	Template:Mono	11	Fuel pressure control system
Template:Mono	Template:Mono	9	Injection pressure control system
Template:Mono	Template:Mono	3	Turbocharger compressor inlet pressure
Template:Mono	Template:Mono	10	Boost pressure control
Template:Mono	Template:Mono	6	Variable Geometry turbo (VGT) control
Template:Mono	Template:Mono	5	Wastegate control
Template:Mono	Template:Mono	5	Exhaust pressure
Template:Mono	Template:Mono	5	Turbocharger RPM
Template:Mono	Template:Mono	7	Turbocharger temperature
Template:Mono	Template:Mono	7	Turbocharger temperature
Template:Mono	Template:Mono	5	Charge air cooler temperature (CACT)
Template:Mono	Template:Mono	9	Exhaust Gas temperature (EGT) Bank 1				Special PID. See below
Template:Mono	Template:Mono	9	Exhaust Gas temperature (EGT) Bank 2				Special PID. See below
Template:Mono	Template:Mono	7	Diesel particulate filter (DPF) differential pressure
Template:Mono	Template:Mono	7	Diesel particulate filter (DPF)
Template:Mono	Template:Mono	9	Diesel Particulate filter (DPF) temperature			°C	$\frac{256A+B}{10}-40$
Template:Mono	Template:Mono	1	NOx NTE (Not-To-Exceed) control area status
Template:Mono	Template:Mono	1	PM NTE (Not-To-Exceed) control area status
Template:Mono	Template:Mono	13	Engine run time Template:Efn			s	$B(2^{24})+C(2^{16})+D(2^8)+E$
Template:Mono	Template:Mono	4	PIDs supported [$81 - $A0]				Bit encoded [A7..D0] == [PID $81..PID $A0] See below
Template:Mono	Template:Mono	41	Engine run time for Auxiliary Emissions Control Device(AECD)
Template:Mono	Template:Mono	41	Engine run time for Auxiliary Emissions Control Device(AECD)
Template:Mono	Template:Mono	9	NOx sensor
Template:Mono	Template:Mono	1	Manifold surface temperature
Template:Mono	Template:Mono	10	NOx reagent system			%	$\frac{100}{255}F$
Template:Mono	Template:Mono	5	Particulate matter (PM) sensor
Template:Mono	Template:Mono	5	Intake manifold absolute pressure
Template:Mono	Template:Mono	13	SCR Induce System
Template:Mono	Template:Mono	41	Run Time for AECD #11-#15
Template:Mono	Template:Mono	41	Run Time for AECD #16-#20
Template:Mono	Template:Mono	7	Diesel Aftertreatment
Template:Mono	Template:Mono	17	O2 Sensor (Wide Range)
Template:Mono	Template:Mono	1	Throttle Position G	0	100	%
Template:Mono	Template:Mono	1	Engine Friction - Percent Torque	-125	130	%	$A-125$
Template:Mono	Template:Mono	7	PM Sensor Bank 1 & 2
Template:Mono	Template:Mono	3	WWH-OBD Vehicle OBD System Information			h
Template:Mono	Template:Mono	5	WWH-OBD Vehicle OBD System Information			h
Template:Mono	Template:Mono	2	Fuel System Control
Template:Mono	Template:Mono	3	WWH-OBD Vehicle OBD Counters support			h
Template:Mono	Template:Mono	12	NOx Warning And Inducement System
Template:Mono	Template:Mono	9	Exhaust Gas Temperature Sensor
Template:Mono	Template:Mono	9	Exhaust Gas Temperature Sensor
Template:Mono	Template:Mono	6	Hybrid/EV Vehicle System Data, Battery, Voltage
Template:Mono	Template:Mono	4	Diesel Exhaust Fluid Sensor Data			%	$\frac{100}{255}D$
Template:Mono	Template:Mono	17	O2 Sensor Data
Template:Mono	Template:Mono	4	Engine Fuel Rate			g/s
Template:Mono	Template:Mono	2	Engine Exhaust Flow Rate			kg/h
Template:Mono	Template:Mono	9	Fuel System Percentage Use
Template:Mono	Template:Mono	4	PIDs supported [$A1 - $C0]				Bit encoded [A7..D0] == [PID $A1..PID $C0] See below
Template:Mono	Template:Mono	9	NOx Sensor Corrected Data			ppm
Template:Mono	Template:Mono	2	Cylinder Fuel Rate	0	2047.96875	mg/stroke	$\frac{256A+B}{32}$
Template:Mono	Template:Mono	9	Evap System Vapor Pressure			Pa
Template:Mono	Template:Mono	4	Transmission Actual Gear	0	65.535	ratio	[A1]==Supported $\frac{256C+D}{1000}$
Template:Mono	Template:Mono	4	Commanded Diesel Exhaust Fluid Dosing	0	127.5	%	[A0]= 1:Supported; 0:Unsupported $\frac{B}{2}$
Template:Mono	Template:Mono	4	Odometer Template:Efn	0	429,496,729.5	km	$\frac{A(2^{24})+B(2^{16})+C(2^8)+D}{10}$
Template:Mono	Template:Mono	4	NOx Sensor Concentration Sensors 3 and 4
Template:Mono	Template:Mono	4	NOx Sensor Corrected Concentration Sensors 3 and 4
Template:Mono	Template:Mono	4	ABS Disable Switch State				[A0]= 1:Supported; 0:Unsupported [B0]= 1:Yes;0:No
Template:Mono	Template:Mono	4	PIDs supported [$C1 - $E0]				Bit encoded [A7..D0] == [PID $C1..PID $E0] See below
Template:Mono	Template:Mono	2	Fuel Level Input A/B	0	25,700	%	Returns numerous data, including Drive Condition ID and Engine Speed*
Template:Mono	Template:Mono	8	Exhaust Particulate Control System Diagnostic Time/Count	0	4,294,967,295	seconds / Count	B5 is Engine Idle Request B6 is Engine Stop Request* First byte = Time in seconds Second byte = Count
Template:Mono	Template:Mono	4	Fuel Pressure A and B	0	5,177	kPa
Template:Mono	Template:Mono	7	Byte 1 - Particulate control - driver inducement system status Byte 2,3 - Removal or block of the particulate aftertreatment system counter Byte 4,5 - Liquid regent injection system (e.g. fuel-borne catalyst) failure counter Byte 6,7 - Malfunction of Particulate control monitoring system counter	0	65,535	h
Template:Mono	Template:Mono	2	Distance Since Reflash or Module Replacement	0	65,535	km
Template:Mono	Template:Mono	1	NOx Control Diagnostic (NCD) and Particulate Control Diagnostic (PCD) Warning Lamp status	-	-	Bit
PID (hex)	PID (Dec)	Data bytes returned	Description	Min value	Max value	Units	FormulaTemplate:Efn

Service Template:Mono - Show freeze frame data

Service Template:Mono accepts the same PIDs as service Template:Mono, with the same meaning, but information given is from when the freeze frame was created. Note that PID Template:Mono is used to obtain the DTC that triggered the freeze frame.

A person has to send the frame number in the data section of the message.

Service Template:Mono - Show stored Diagnostic Trouble Codes (DTCs)

PID (hex)	Data bytes returned	Description	Min value	Max value	Units	FormulaTemplate:Efn
N/A	n*6	Request trouble codes				3 codes per message frame. See below

Service Template:Mono - Clear Diagnostic Trouble Codes and stored values

PID (hex)	Data bytes returned	Description	Min value	Max value	Units	FormulaTemplate:Efn
N/A	0	Clear trouble codes / Malfunction indicator lamp (MIL) / Check engine light				Clears all stored trouble codes and turns the MIL off.

Service Template:Mono - Test results, oxygen sensor monitoring (non CAN only)

PID (hex)	Data bytes returned	Description	Min value	Max value	Units	FormulaTemplate:Efn
Template:Mono	4	OBD Monitor IDs supported ($01 – $20)	0x0	0xffffffff
Template:Mono	2	O2 Sensor Monitor Bank 1 Sensor 1	0.00	1.275	V	0.005 Rich to lean sensor threshold voltage
Template:Mono		O2 Sensor Monitor Bank 1 Sensor 2	0.00	1.275	V	0.005 Rich to lean sensor threshold voltage
Template:Mono		O2 Sensor Monitor Bank 1 Sensor 3	0.00	1.275	V	0.005 Rich to lean sensor threshold voltage
Template:Mono		O2 Sensor Monitor Bank 1 Sensor 4	0.00	1.275	V	0.005 Rich to lean sensor threshold voltage
Template:Mono		O2 Sensor Monitor Bank 2 Sensor 1	0.00	1.275	V	0.005 Rich to lean sensor threshold voltage
Template:Mono		O2 Sensor Monitor Bank 2 Sensor 2	0.00	1.275	V	0.005 Rich to lean sensor threshold voltage
Template:Mono		O2 Sensor Monitor Bank 2 Sensor 3	0.00	1.275	V	0.005 Rich to lean sensor threshold voltage
Template:Mono		O2 Sensor Monitor Bank 2 Sensor 4	0.00	1.275	V	0.005 Rich to lean sensor threshold voltage
Template:Mono		O2 Sensor Monitor Bank 3 Sensor 1	0.00	1.275	V	0.005 Rich to lean sensor threshold voltage
Template:Mono		O2 Sensor Monitor Bank 3 Sensor 2	0.00	1.275	V	0.005 Rich to lean sensor threshold voltage
Template:Mono		O2 Sensor Monitor Bank 3 Sensor 3	0.00	1.275	V	0.005 Rich to lean sensor threshold voltage
Template:Mono		O2 Sensor Monitor Bank 3 Sensor 4	0.00	1.275	V	0.005 Rich to lean sensor threshold voltage
Template:Mono		O2 Sensor Monitor Bank 4 Sensor 1	0.00	1.275	V	0.005 Rich to lean sensor threshold voltage
Template:Mono		O2 Sensor Monitor Bank 4 Sensor 2	0.00	1.275	V	0.005 Rich to lean sensor threshold voltage
Template:Mono		O2 Sensor Monitor Bank 4 Sensor 3	0.00	1.275	V	0.005 Rich to lean sensor threshold voltage
Template:Mono		O2 Sensor Monitor Bank 4 Sensor 4	0.00	1.275	V	0.005 Rich to lean sensor threshold voltage
Template:Mono		O2 Sensor Monitor Bank 1 Sensor 1	0.00	1.275	V	0.005 Lean to Rich sensor threshold voltage
Template:Mono		O2 Sensor Monitor Bank 1 Sensor 2	0.00	1.275	V	0.005 Lean to Rich sensor threshold voltage
Template:Mono		O2 Sensor Monitor Bank 1 Sensor 3	0.00	1.275	V	0.005 Lean to Rich sensor threshold voltage
Template:Mono		O2 Sensor Monitor Bank 1 Sensor 4	0.00	1.275	V	0.005 Lean to Rich sensor threshold voltage
Template:Mono		O2 Sensor Monitor Bank 2 Sensor 1	0.00	1.275	V	0.005 Lean to Rich sensor threshold voltage
Template:Mono		O2 Sensor Monitor Bank 2 Sensor 2	0.00	1.275	V	0.005 Lean to Rich sensor threshold voltage
Template:Mono		O2 Sensor Monitor Bank 2 Sensor 3	0.00	1.275	V	0.005 Lean to Rich sensor threshold voltage
Template:Mono		O2 Sensor Monitor Bank 2 Sensor 4	0.00	1.275	V	0.005 Lean to Rich sensor threshold voltage
Template:Mono		O2 Sensor Monitor Bank 3 Sensor 1	0.00	1.275	V	0.005 Lean to Rich sensor threshold voltage
Template:Mono		O2 Sensor Monitor Bank 3 Sensor 2	0.00	1.275	V	0.005 Lean to Rich sensor threshold voltage
Template:Mono		O2 Sensor Monitor Bank 3 Sensor 3	0.00	1.275	V	0.005 Lean to Rich sensor threshold voltage
Template:Mono		O2 Sensor Monitor Bank 3 Sensor 4	0.00	1.275	V	0.005 Lean to Rich sensor threshold voltage
Template:Mono		O2 Sensor Monitor Bank 4 Sensor 1	0.00	1.275	V	0.005 Lean to Rich sensor threshold voltage
Template:Mono		O2 Sensor Monitor Bank 4 Sensor 2	0.00	1.275	V	0.005 Lean to Rich sensor threshold voltage
Template:Mono		O2 Sensor Monitor Bank 4 Sensor 3	0.00	1.275	V	0.005 Lean to Rich sensor threshold voltage
Template:Mono		O2 Sensor Monitor Bank 4 Sensor 4	0.00	1.275	V	0.005 Lean to Rich sensor threshold voltage
PID (hex)	Data bytes returned	Description	Min value	Max value	Units	FormulaTemplate:Efn

Service Template:Mono - Request vehicle information

PID (hex)	Data bytes returned	Description	Min value	Max value	Units	FormulaTemplate:Efn
Template:Mono	4	Service 9 supported PIDs ($01 to $20)				Bit encoded. [A7..D0] = [PID $01..PID $20] See below
Template:Mono	1	VIN Message Count in PID Template:Mono. Only for ISO 9141-2, ISO 14230-4 and SAE J1850.				Usually the value will be 5.
Template:Mono	17	Vehicle Identification Number (VIN)				17-char VIN, ASCII-encoded and left-padded with null chars (Template:Mono) if needed to.
Template:Mono	1	Calibration ID message count for PID Template:Mono. Only for ISO 9141-2, ISO 14230-4 and SAE J1850.				It will be a multiple of 4 (4 messages are needed for each ID).
Template:Mono	16,32,48,64..	Calibration ID				Up to 16 ASCII chars. Data bytes not used will be reported as null bytes (Template:Mono). Several CALID can be outputed (16 bytes each)
Template:Mono	1	Calibration verification numbers (CVN) message count for PID Template:Mono. Only for ISO 9141-2, ISO 14230-4 and SAE J1850.
Template:Mono	4,8,12,16	Calibration Verification Numbers (CVN) Several CVN can be output (4 bytes each) the number of CVN and CALID must match				Raw data left-padded with null characters (Template:Mono). Usually displayed as hex string.
Template:Mono	1	In-use performance tracking message count for PID Template:Mono and Template:Mono. Only for ISO 9141-2, ISO 14230-4 and SAE J1850.	8	10		8 if sixteen values are required to be reported, 9 if eighteen values are required to be reported, and 10 if twenty values are required to be reported (one message reports two values, each one consisting in two bytes).
Template:Mono	4	In-use performance tracking for spark ignition vehicles				4 or 5 messages, each one containing 4 bytes (two values). See below
Template:Mono	1	ECU name message count for PID Template:Mono
Template:Mono	20	ECU name				ASCII-coded. Right-padded with null chars (Template:Mono).
Template:Mono	4	In-use performance tracking for compression ignition vehicles				5 messages, each one containing 4 bytes (two values). See below
PID (hex)	Data bytes returned	Description	Min value	Max value	Units	FormulaTemplate:Efn

Bitwise encoded PIDs

Some of the PIDs in the above table cannot be explained with a simple formula. A more elaborate explanation of these data is provided here:

Service 01 PID Template:Mono - Show PIDs supported

A request for this PID returns 4 bytes of data (Big-endian). Each bit, from MSB to LSB, represents one of the next 32 PIDs and specifies whether that PID is supported.

For example, if the car response is Template:Mono, it can be decoded like this:

Hexadecimal	Template:Mono				Template:Mono				Template:Mono				Template:Mono				Template:Mono				Template:Mono				Template:Mono				Template:Mono
Binary	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono
Supported?	Template:Yes	Template:No	Template:Yes	Template:Yes	Template:Yes	Template:Yes	Template:Yes	Template:No	Template:No	Template:No	Template:No	Template:Yes	Template:Yes	Template:Yes	Template:Yes	Template:Yes	Template:Yes	Template:No	Template:Yes	Template:No	Template:Yes	Template:No	Template:No	Template:No	Template:No	Template:No	Template:No	Template:Yes	Template:No	Template:No	Template:Yes	Template:Yes
PID number	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono

So, supported PIDs are: Template:Mono, Template:Mono, Template:Mono, Template:Mono, Template:Mono, Template:Mono, Template:Mono, Template:Mono, Template:Mono, Template:Mono, Template:Mono, Template:Mono, Template:Mono, Template:Mono, Template:Mono, Template:Mono and Template:Mono

Service 01 PID Template:Mono - Monitor status since DTCs cleared

A request for this PID returns 4 bytes of data, labeled A, B, C and D.

The first byte (A) contains two pieces of information. Bit Template:Mono (MSB of byte A) indicates whether or not the MIL (malfunction indicator light, aka. check engine light) is illuminated. Bits Template:Mono through Template:Mono represent the number of diagnostic trouble codes currently flagged in the ECU.

The second, third, and fourth bytes (B, C and D) give information about the availability and completeness of certain on-board tests ("OBD readiness checks"). The third and fourth bytes are to be interpreted differently depending upon whether the engine is spark ignition (e.g. Otto or Wankel engines) or compression ignition (e.g. Diesel engines). In the second byte (B), bit Template:Mono indicates the engine type and thus how to interpret bytes C and D, with Template:Mono being spark (Otto or Wankel) and Template:Mono (set) being compression (Diesel). Bits Template:Mono to Template:Mono and Template:Mono to Template:Mono are used for information about tests that not engine-type specific, and thus termed common tests. Note that for bits indicating test availability a bit set to Template:Mono indicates available, whilst for bits indicating test completeness a bit set to Template:Mono indicates complete.

Bits	Definition
Template:Mono	State of the CEL/MIL (on/off).
Template:Mono-Template:Mono	Number of confirmed emissions-related DTCs available for display.
Template:Mono	Reserved (should be Template:Mono)
Template:Mono-Template:Mono	Bitmap indicating completeness of common tests.
Template:Mono	Indication of engine type Template:Mono = Spark ignition (e.g. Otto or Wankel engines) Template:Mono = Compression ignition (e.g. Diesel engines)
Template:Mono-Template:Mono	Bitmap indicating availability of common tests.
Template:Mono-Template:Mono	Bitmap indicating availability of engine-type specific tests.
Template:Mono-Template:Mono	Bitmap indicating completeness of engine-type specific tests.

Bits from byte B representing common test indicators (those not engine-type specific) are mapped as follows:

	Test availability	Test completeness
Components	Template:Mono	Template:Mono
Fuel System	Template:Mono	Template:Mono
Misfire	Template:Mono	Template:Mono

Bytes C and D are mapped as follows for spark ignition engine types (e.g. Otto or Wankel engines):

	Test availability	Test completeness
EGR and/or VVT System	Template:Mono	Template:Mono
Oxygen Sensor Heater	Template:Mono	Template:Mono
Oxygen Sensor	Template:Mono	Template:Mono
Gasoline Particulate FilterTemplate:Efn	Template:Mono	Template:Mono
Secondary Air System	Template:Mono	Template:Mono
Evaporative System	Template:Mono	Template:Mono
Heated Catalyst	Template:Mono	Template:Mono
Catalyst	Template:Mono	Template:Mono

Bytes C and D are alternatively mapped as follows for compression ignition engine types (Diesel engines):

	Test availability	Test completeness
EGR and/or VVT System	Template:Mono	Template:Mono
PM filter monitoring	Template:Mono	Template:Mono
Exhaust Gas Sensor	Template:Mono	Template:Mono
- Reserved -	Template:Mono	Template:Mono
Boost Pressure	Template:Mono	Template:Mono
- Reserved -	Template:Mono	Template:Mono
NOx/SCR Monitor	Template:Mono	Template:Mono
NMHC CatalystTemplate:Efn	Template:Mono	Template:Mono

Service 01 PID Template:Mono - Monitor status this drive cycle

A request for this PID returns 4 bytes of data. The data returned is of an identical form to that returned for PID Template:Mono, with one exception - the first byte is always zero.

Service 01 PID 78 and 79 - Exhaust Gas temperature (EGT) Bank 1 and Bank 2

A request for one of these two PIDs will return 9 bytes of data. PID Template:Mono returns data relating to EGT sensors for bank 1, whilst PID Template:Mono similarly returns data for bank 2. The first byte is a bit encoded field indicating which EGT sensors are supported for the respective bank.

Bytes	Description
Template:Mono	EGT sensor support
Template:Mono-Template:Mono	Temperature read by EGT sensor 1
Template:Mono-Template:Mono	Temperature read by EGT sensor 2
Template:Mono-Template:Mono	Temperature read by EGT sensor 3
Template:Mono-Template:Mono	Temperature read by EGT sensor 4

The first byte is bit-encoded as follows:

Bits	Description
Template:Mono-Template:Mono	Reserved
Template:Mono	EGT sensor 4 supported?
Template:Mono	EGT sensor 3 supported?
Template:Mono	EGT sensor 2 supported?
Template:Mono	EGT sensor 1 supported?

Bytes B through I provide 16-bit integers indicating the temperatures of the sensors. The temperature values are interpreted in degrees Celsius in the range -40 to 6513.5 (scale 0.1), using the usual $(A\times 256+B)/10-40$ formula (MSB is A, LSB is B). Only values for which the corresponding sensor is supported are meaningful.

Service 03 (no PID required) - Show stored Diagnostic Trouble Codes

A request for this service returns a list of the DTCs that have been set. The list is encapsulated using the ISO 15765-2 protocol.

If there are two or fewer DTCs (up to 4 bytes) then they are returned in an ISO-TP Single Frame (SF). Three or more DTCs in the list are reported in multiple frames, with the exact count of frames dependent on the communication type and addressing details.

Each trouble code requires 2 bytes to describe. Encoded in these bytes are a category and a number. It is typically shown decoded into a five-character form like "Template:Mono", where the first character (here 'U') represents the category the DTC belongs to, and the remaining four characters are a hexadecimal representation of the number under that category. The first two bits (Template:Mono and Template:Mono) of the first byte (A) represent the category. The remaining 14 bits represent the number. Of note is that since the second character is formed from only two bits, it can thus only be within the range Template:Mono-Template:Mono.

Bits	Definition
Template:Mono-Template:Mono	Category Template:Mono: Template:Mono - Powertrain Template:Mono: Template:Mono - Chassis Template:Mono: Template:Mono - Body Template:Mono: Template:Mono - NetworkTemplate:Efn
Template:Mono-Template:Mono	Number (within category)

An example DTC of "Template:Mono" would be decoded as follows:

Bit	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono
Binary	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono	Template:Mono
Hexadecimal	Template:Mono				Template:Mono				Template:Mono				Template:Mono
Decoded DTC	Template:Mono		Template:Mono		Template:Mono				Template:Mono				Template:Mono

The resulting five-character code, e.g. "Template:Mono", can be looked up in a table of OBD-II DTCs to get an actual description of what it represents. Of note, whilst some blocks of DTC code ranges have generic meanings that apply to all vehicles and manufacturers, the meanings of others can vary per manufacturer or even model.

It is also worth noting that DTCs may sometimes be encountered in a four-character form, e.g. "Template:Mono", which is simply the plain hexadecimal representation of the two bytes, with proper decoding with respect to the category not having been performed.

Service 09 PID 08 - In-use performance tracking for spark ignition engines

It provides information about track in-use performance for catalyst banks, oxygen sensor banks, evaporative leak detection systems, EGR systems and secondary air system.

The numerator for each component or system tracks the number of times that all conditions necessary for a specific monitor to detect a malfunction have been encountered. The denominator for each component or system tracks the number of times that the vehicle has been operated in the specified conditions.

The count of data items should be reported at the beginning (the first byte).

All data items of the In-use Performance Tracking record consist of two bytes and are reported in this order (each message contains two items, hence the message length is 4).

Mnemonic	Description
OBDCOND	OBD Monitoring Conditions Encountered Counts
IGNCNTR	Ignition Counter
CATCOMP1	Catalyst Monitor Completion Counts Bank 1
CATCOND1	Catalyst Monitor Conditions Encountered Counts Bank 1
CATCOMP2	Catalyst Monitor Completion Counts Bank 2
CATCOND2	Catalyst Monitor Conditions Encountered Counts Bank 2
O2SCOMP1	O2 Sensor Monitor Completion Counts Bank 1
O2SCOND1	O2 Sensor Monitor Conditions Encountered Counts Bank 1
O2SCOMP2	O2 Sensor Monitor Completion Counts Bank 2
O2SCOND2	O2 Sensor Monitor Conditions Encountered Counts Bank 2
EGRCOMP	EGR Monitor Completion Condition Counts
EGRCOND	EGR Monitor Conditions Encountered Counts
AIRCOMP	AIR Monitor Completion Condition Counts (Secondary Air)
AIRCOND	AIR Monitor Conditions Encountered Counts (Secondary Air)
EVAPCOMP	EVAP Monitor Completion Condition Counts
EVAPCOND	EVAP Monitor Conditions Encountered Counts
SO2SCOMP1	Secondary O2 Sensor Monitor Completion Counts Bank 1
SO2SCOND1	Secondary O2 Sensor Monitor Conditions Encountered Counts Bank 1
SO2SCOMP2	Secondary O2 Sensor Monitor Completion Counts Bank 2
SO2SCOND2	Secondary O2 Sensor Monitor Conditions Encountered Counts Bank 2

Service 09 PID 0B - In-use performance tracking for compression ignition engines

It provides information about track in-use performance for NMHC catalyst, NOx catalyst monitor, NOx adsorber monitor, PM filter monitor, exhaust gas sensor monitor, EGR/ VVT monitor, boost pressure monitor and fuel system monitor.

All data items consist of two bytes and are reported in this order (each message contains two items, hence message length is 4):

Mnemonic	Description
OBDCOND	OBD Monitoring Conditions Encountered Counts
IGNCNTR	Ignition Counter
HCCATCOMP	NMHC Catalyst Monitor Completion Condition Counts
HCCATCOND	NMHC Catalyst Monitor Conditions Encountered Counts
NCATCOMP	NOx/SCR Catalyst Monitor Completion Condition Counts
NCATCOND	NOx/SCR Catalyst Monitor Conditions Encountered Counts
NADSCOMP	NOx Adsorber Monitor Completion Condition Counts
NADSCOND	NOx Adsorber Monitor Conditions Encountered Counts
PMCOMP	PM Filter Monitor Completion Condition Counts
PMCOND	PM Filter Monitor Conditions Encountered Counts
EGSCOMP	Exhaust Gas Sensor Monitor Completion Condition Counts
EGSCOND	Exhaust Gas Sensor Monitor Conditions Encountered Counts
EGRCOMP	EGR and/or VVT Monitor Completion Condition Counts
EGRCOND	EGR and/or VVT Monitor Conditions Encountered Counts
BPCOMP	Boost Pressure Monitor Completion Condition Counts
BPCOND	Boost Pressure Monitor Conditions Encountered Counts
FUELCOMP	Fuel Monitor Completion Condition Counts
FUELCOND	Fuel Monitor Conditions Encountered Counts

Enumerated PIDs

Some PIDs are to be interpreted specially, and aren't necessarily exactly bitwise encoded, or in any scale. The values for these PIDs are enumerated.

Service 01 PID Template:Mono - Fuel system status

A request for this PID returns 2 bytes of data. The first byte describes fuel system #1. The second byte describes fuel system #2 (if it exists) and is encoded identically to the first byte. The meaning assigned to the value of each byte is as follows:

Value	Description
0	The motor is off
1	Open loop due to insufficient engine temperature
2	Closed loop, using oxygen sensor feedback to determine fuel mix
4	Open loop due to engine load OR fuel cut due to deceleration
8	Open loop due to system failure
16	Closed loop, using at least one oxygen sensor but there is a fault in the feedback system

Any other value is an invalid response.

Service 01 PID Template:Mono - Commanded secondary air status

A request for this PID returns a single byte of data which describes the secondary air status.

Value	Description
1	Upstream
2	Downstream of catalytic converter
4	From the outside atmosphere or off
8	Pump commanded on for diagnostics

Any other value is an invalid response.

Service 01 PID Template:Mono - OBD standards this vehicle conforms to

A request for this PID returns a single byte of data which describes which OBD standards this ECU was designed to comply with. The different values the data byte can hold are shown below, next to what they mean:

Value	Description
1	OBD-II as defined by the CARB
2	OBD as defined by the EPA
3	OBD and OBD-II
4	OBD-I
5	Not OBD compliant
6	EOBD (Europe)
7	EOBD and OBD-II
8	EOBD and OBD
9	EOBD, OBD and OBD II
10	JOBD (Japan)
11	JOBD and OBD II
12	JOBD and EOBD
13	JOBD, EOBD, and OBD II
14	Reserved
15	Reserved
16	Reserved
17	Engine Manufacturer Diagnostics (EMD)
18	Engine Manufacturer Diagnostics Enhanced (EMD+)
19	Heavy Duty On-Board Diagnostics (Child/Partial) (HD OBD-C)
20	Heavy Duty On-Board Diagnostics (HD OBD)
21	World Wide Harmonized OBD (WWH OBD)
22	Reserved
23	Heavy Duty Euro OBD Stage I without NOx control (HD EOBD-I)
24	Heavy Duty Euro OBD Stage I with NOx control (HD EOBD-I N)
25	Heavy Duty Euro OBD Stage II without NOx control (HD EOBD-II)
26	Heavy Duty Euro OBD Stage II with NOx control (HD EOBD-II N)
27	Reserved
28	Brazil OBD Phase 1 (OBDBr-1)
29	Brazil OBD Phase 2 (OBDBr-2)
30	Korean OBD (KOBD)
31	India OBD I (IOBD I)
32	India OBD II (IOBD II)
33	Heavy Duty Euro OBD Stage VI (HD EOBD-IV)
34-250	Reserved
251-255	Not available for assignment (SAE J1939 special meaning)

Service 01 PID Template:Mono - Fuel Type Coding

This PID returns a value from an enumerated list giving the fuel type of the vehicle. The fuel type is returned as a single byte, and the value is given by the following table:

Value	Description
0	Not available
1	Gasoline
2	Methanol
3	Ethanol
4	Diesel
5	LPG
6	CNG
7	Propane
8	Electric
9	Bifuel running Gasoline
10	Bifuel running Methanol
11	Bifuel running Ethanol
12	Bifuel running LPG
13	Bifuel running CNG
14	Bifuel running Propane
15	Bifuel running Electricity
16	Bifuel running electric and combustion engine
17	Hybrid gasoline
18	Hybrid Ethanol
19	Hybrid Diesel
20	Hybrid Electric
21	Hybrid running electric and combustion engine
22	Hybrid Regenerative
23	Bifuel running diesel

Any other value is reserved by ISO/SAE. There are currently no definitions for flexible-fuel vehicle.

Non-standard PIDs

The majority of all OBD-II PIDs in use are non-standard. For most modern vehicles, there are many more functions supported on the OBD-II interface than are covered by the standard PIDs, and there is relatively minor overlap between vehicle manufacturers for these non-standard PIDs.

There is very limited information available in the public domain for non-standard PIDs. The primary source of information on non-standard PIDs across different manufacturers is maintained by the US-based Equipment and Tool Institute and only available to members. The price of ETI membership for access to scan codes varies based on company size defined by annual sales of automotive tools and equipment in North America:

Annual Sales in North America	Annual Dues
Under $10,000,000	$5,000
$10,000,000 - $50,000,000	$7,500
Greater than $50,000,000	$10,000

However, even ETI membership will not provide full documentation for non-standard PIDs. ETI states:

Some OEMs refuse to use ETI as a one-stop source of scan tool information. They prefer to do business with each tool company separately. These companies also require that you enter into a contract with them. The charges vary but here is a snapshot as of April 13th, 2015 of the per year charges:

GM	$50,000
Honda	$5,000
Suzuki	$1,000
BMW	$25,500 plus $2,000 per update. Updates occur annually.

CAN (11-bit) bus format

As defined in ISO 15765-4, emissions protocols (including OBD-II, EOBD, UDS, etc.) use the ISO-TP transport layer (ISO 15765-2). All CAN frames sent using ISO-TP use a data length of 8 bytes (and DLC of 8). It is recommended to pad the unused data bytes with 0xCC.

The PID query and response occurs on the vehicle's CAN bus. Standard OBD requests and responses use functional addresses. The diagnostic reader initiates a query using CAN ID 7DFh, which acts as a broadcast address, and accepts responses from any ID in the range 7E8h to 7EFh. ECUs that can respond to OBD queries listen both to the functional broadcast ID of 7DFh and one assigned ID in the range 7E0h to 7E7h. Their response has an ID of their assigned ID plus 8 e.g. 7E8h through 7EFh.

This approach allows up to eight ECUs, each independently responding to OBD queries. The diagnostic reader can use the ID in the ECU response frame to continue communication with a specific ECU. In particular, multi-frame communication requires a response to the specific ECU ID rather than to ID 7DFh.

CAN bus may also be used for communication beyond the standard OBD messages. Physical addressing uses particular CAN IDs for specific modules (e.g., 720h for the instrument cluster in Fords) with proprietary frame payloads.

Query

The functional PID query is sent to the vehicle on the CAN bus at ID 7DFh, using 8 data bytes. The bytes are:

	Byte
PID Type	0	1	2	3	4	5	6	7
SAE Standard	Number of additional data bytes: 2	Service 01 = show current data; 02 = freeze frame; etc.	PID code (e.g.: 05 = Engine coolant temperature)	not used (ISO 15765-2 suggests CCh)
Vehicle specific	Number of additional data bytes: 3	Custom service: (e.g.: 22 = enhanced data)	PID code (e.g.: 4980h)		not used (ISO 15765-2 suggests CCh)

Response

The vehicle responds to the PID query on the CAN bus with message IDs that depend on which module responded. Typically the engine or main ECU responds at ID 7E8h. Other modules, like the hybrid controller or battery controller in a Prius, respond at 07E9h, 07EAh, 07EBh, etc. These are 8h higher than the physical address the module responds to. Even though the number of bytes in the returned value is variable, the message uses 8 data bytes regardless (CAN bus protocol form Frameformat with 8 data bytes). The bytes are:

	Byte
CAN Address	0	1	2	3	4	5	6	7
SAE Standard 7E8h, 7E9h, 7EAh, etc.	Number of additional data bytes: 3 to 6	Custom service Same as query, except that 40h is added to the service value. So: 41h = show current data; 42h = freeze frame; etc.	PID code (e.g.: 05 = Engine coolant temperature)	value of the specified parameter, byte 0	value, byte 1 (optional)	value, byte 2 (optional)	value, byte 3 (optional)	not used (may be 00h or 55h)
Vehicle specific 7E8h, or 8h + physical ID of module.	Number of additional data bytes: 4to 7	Custom service: same as query, except that 40h is added to the service value.(e.g.: 62h = response to service 22h request)	PID code (e.g.: 4980h)		value of the specified parameter, byte 0	value, byte 1 (optional)	value, byte 2 (optional)	value, byte 3 (optional)
Vehicle specific 7E8h, or 8h + physical ID of module.	Number of additional data bytes: 3	7Fh this a general response usually indicating the module doesn't recognize the request.	Custom service: (e.g.: 22h = enhanced diagnostic data by PID, 21h = enhanced data by offset)	31h	not used (may be 00h)

See also

• Engine control unit
• ELM327, a very common microcontroller (silicon chip) and multi-protocol interpreter used in OBD-II vehicle communication interfaces
• Unified Diagnostic Services, the ISO standard

Further reading

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