OBD-II PIDs
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P-codes, or OBD-II PIDs On Board Diagnostics "Parameter IDs", are codes used to request data from a vehicle, used as a diagnostic tool. These codes are part of SAE standard J/1979, required to be implemented in all cars sold in North America since 1996.

Typically, a car mechanic will use PIDs with a scan tool connected to the vehicle's OBD-II connector.

  • The mechanic enters the PID
  • The scan tool sends to the vehicle's bus (CAN, VPW, PWM, ISO, KWP. After 2008, CAN only)
  • A device on the bus recognizes the PID as one it is responsible for, and reports the value for that PID to the bus
  • The scan tool reads the response, and shows it to the mechanic

Contents

Modes

There are nine modes of operation described in the OBD-II standard SAE J1979. They are:

  1. Show current data
  2. Show freeze frame data
  3. Show stored Diagnostic Trouble Codes
  4. Clear Diagnostic Trouble Codes and stored values
  5. Test results, oxygen sensor monitoring
  6. Test results, other component/system monitoring (e.g.: Catalyst, EVAP)
  7. Show pending Diagnostic Trouble Codes (detected during current or last driving cycle)
  8. Control operation of on-board component/system
  9. Request vehicle information


Vehicle manufactures are not required to support all modes.

Each manufacturer may define additional modes above #9 (e.g.: mode 22 as defined by SAE J2190 for Ford/GM, mode 21 for Toyota) for other information (e.g.: the voltage of the Traction Battery in a HEV).

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 modes 1 and 2 are basically identical, except that Mode 1 provides current information, whereas Mode 2 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 Mode 1, and PID 02, which is only available in Mode 2. If Mode 2 PID 02 returns zero, then there is no snapshot and all other Mode 2 data is meaningless.

Mode
(hex)		 PID
(hex)		 Data bytes returned Description Min value Max value Units Formula
01 00 4 PIDs supported Bit encoded [A7..D0] == [PID 0x01..PID 0x20]
01 01 4 Monitor status since DTCs cleared. (Includes malfunction indicator lamp (MIL) status and number of DTCs.) Bit encoded. See below.
01 02 8 Freeze DTC
01 03 2 Fuel system status Bit encoded. See below.
01 04 1 Calculated engine load value 0 100  % A*100/255
01 05 1 Engine coolant temperature -40 215 °C A-40
01 06 1 Short term fuel % trim—Bank 1 -100 (Rich) 99.22 (Lean)  % (A-128) * 100/128
01 07 1 Long term fuel % trim—Bank 1 -100 (Rich) 99.22 (Lean)  % (A-128) * 100/128
01 08 1 Short term fuel % trim—Bank 2 -100 (Rich) 99.22 (Lean)  % (A-128) * 100/128
01 09 1 Long term fuel % trim—Bank 2 -100 (Rich) 99.22 (Lean)  % (A-128) * 100/128
01 0A 1 Fuel pressure 0 765 kPa (gauge) A*3
01 0B 1 Intake manifold pressure 0 255 kPa (absolute) A
01 0C 2 Engine RPM 0 16,383.75 rpm ((A*256)+B)/4
01 0D 1 Vehicle speed 0 255 km/h A
01 0E 1 Timing advance -64 63.5 ° relative to #1 cylinder A/2 - 64
01 0F 1 Intake air temperature -40 215 °C A-40
01 10 2 MAF air flow rate 0 655.35 g/s ((256*A)+B) / 100
01 11 1 Throttle position 0 100  % A*100/255
01 12 1 Commanded secondary air status Bit encoded. See below.
01 13 1 Oxygen sensors present [A0..A3] == Bank 1, Sensors 1-4. [A4..A7] == Bank 2...
01 14 2 Bank 1, Sensor 1:
Oxygen sensor voltage,
Short term fuel trim		 0
0		 1.275
99.2		 Volts
%		 A * 0.005
(B-128) * 100/128 (if B==0xFF, sensor is not used in trim calc)
01 15 2 Bank 1, Sensor 2:
Oxygen sensor voltage,
Short term fuel trim		 0
0		 1.275
99.2		 Volts
%		 A * 0.005
(B-128) * 100/128 (if B==0xFF, sensor is not used in trim calc)
01 16 2 Bank 1, Sensor 3:
Oxygen sensor voltage,
Short term fuel trim		 0
0		 1.275
99.2		 Volts
%		 A * 0.005
(B-128) * 100/128 (if B==0xFF, sensor is not used in trim calc)
01 17 2 Bank 1, Sensor 4:
Oxygen sensor voltage,
Short term fuel trim		 0
0		 1.275
99.2		 Volts
%		 A * 0.005
(B-128) * 100/128 (if B==0xFF, sensor is not used in trim calc)
01 18 2 Bank 2, Sensor 1:
Oxygen sensor voltage,
Short term fuel trim		 0
0		 1.275
99.2		 Volts
%		 A * 0.005
(B-128) * 100/128 (if B==0xFF, sensor is not used in trim calc)
01 19 2 Bank 2, Sensor 2:
Oxygen sensor voltage,
Short term fuel trim		 0
0		 1.275
99.2		 Volts
%		 A * 0.005
(B-128) * 100/128 (if B==0xFF, sensor is not used in trim calc)
01 1A 2 Bank 2, Sensor 3:
Oxygen sensor voltage,
Short term fuel trim		 0
0		 1.275
99.2		 Volts
%		 A * 0.005
(B-128) * 100/128 (if B==0xFF, sensor is not used in trim calc)
01 1B 2 Bank 2, Sensor 4:
Oxygen sensor voltage,
Short term fuel trim		 0
0		 1.275
99.2		 Volts
%		 A * 0.005
(B-128) * 100/128 (if B==0xFF, sensor is not used in trim calc)
01 1C 1 OBD standards this vehicle conforms to Bit encoded. See below.
01 1D 1 Oxygen sensors present Similar to PID 13, but [A0..A7] == [B1S1, B1S2, B2S1, B2S2, B3S1, B3S2, B4S1, B4S2]
01 1E 1 Auxiliary input status A0 == Power Take Off (PTO) status (1 == active)
[A1..A7] not used
01 1F 2 Run time since engine start 0 65,535 seconds (A*256)+B
01 20 4 PIDs supported 21-40 Bit encoded [A7..D0] == [PID 0x21..PID 0x40]
01 21 2 Distance traveled with malfunction indicator lamp (MIL) on 0 65,535 km (A*256)+B
01 22 2 Fuel Rail Pressure (relative to manifold vacuum) 0 5177.265 kPa ((A*256)+B) * 0.079
01 23 2 Fuel Rail Pressure (diesel) 0 655350 kPa (gauge) ((A*256)+B) * 10
01 24 4 O2S1_WR_lambda(1):
Equivalence Ratio
Voltage		 0
0		 2
8		 N/A
V		 ((A*256)+B)*0.0000305
((C*256)+D)*0.000122
01 25 4 O2S2_WR_lambda(1):
Equivalence Ratio
Voltage		 0
0		 2
8		 N/A
V		 ((A*256)+B)*0.0000305
((C*256)+D)*0.000122
01 26 4 O2S3_WR_lambda(1):
Equivalence Ratio
Voltage		 0
0		 2
8		 N/A
V		 ((A*256)+B)*0.0000305
((C*256)+D)*0.000122
01 27 4 O2S4_WR_lambda(1):
Equivalence Ratio
Voltage		 0
0		 2
8		 N/A
V		 ((A*256)+B)*0.0000305
((C*256)+D)*0.000122
01 28 4 O2S5_WR_lambda(1):
Equivalence Ratio
Voltage		 0
0		 2
8		 N/A
V		 ((A*256)+B)*0.0000305
((C*256)+D)*0.000122
01 29 4 O2S6_WR_lambda(1):
Equivalence Ratio
Voltage		 0
0		 2
8		 N/A
V		 ((A*256)+B)*0.0000305
((C*256)+D)*0.000122
01 2A 4 O2S7_WR_lambda(1):
Equivalence Ratio
Voltage		 0
0		 2
8		 N/A
V		 ((A*256)+B)*0.0000305
((C*256)+D)*0.000122
01 2B 4 O2S8_WR_lambda(1):
Equivalence Ratio
Voltage		 0
0		 2
8		 N/A
V		 ((A*256)+B)*0.0000305
((C*256)+D)*0.000122
01 2C 1 Commanded EGR 0 100  % 100*A/255
01 2D 1 EGR Error -100 99.22  % A*0.78125 - 100
01 2E 1 Commanded evaporative purge 0 100  % 100*A/255
01 2F 1 Fuel Level Input 0 100  % 100*A/255
01 30 1 # of warm-ups since codes cleared 0 255 N/A A
01 31 2 Distance traveled since codes cleared 0 65,535 km (A*256)+B
01 32 2 Evap. System Vapor Pressure -8,192 8,192 Pa ((A*256)+B)/4 - 8,192
01 33 1 Barometric pressure 0 255 kPa (Absolute) A
01 34 4 O2S1_WR_lambda(1):
Equivalence Ratio
Current		 0
-128		 2
128		 N/A
mA		 ((A*256)+B)*0.0000305
((C*256)+D)*0.00390625 - 128
01 35 4 O2S2_WR_lambda(1):
Equivalence Ratio
Current		 0
-128		 2
128		 N/A
mA		 ((A*256)+B)*0.0000305
((C*256)+D)*0.00390625 - 128
01 36 4 O2S3_WR_lambda(1):
Equivalence Ratio
Current		 0
-128		 2
128		 N/A
mA		 ((A*256)+B)*0.0000305
((C*256)+D)*0.00390625 - 128
01 37 4 O2S4_WR_lambda(1):
Equivalence Ratio
Current		 0
-128		 2
128		 N/A
mA		 ((A*256)+B)*0.0000305
((C*256)+D)*0.00390625 - 128
01 38 4 O2S5_WR_lambda(1):
Equivalence Ratio
Current		 0
-128		 2
128		 N/A
mA		 ((A*256)+B)*0.0000305
((C*256)+D)*0.00390625 - 128
01 39 4 O2S6_WR_lambda(1):
Equivalence Ratio
Current		 0
-128		 2
128		 N/A
mA		 ((A*256)+B)*0.0000305
((C*256)+D)*0.00390625 - 128
01 3A 4 O2S7_WR_lambda(1):
Equivalence Ratio
Current		 0
-128		 2
128		 N/A
mA		 ((A*256)+B)*0.0000305
((C*256)+D)*0.00390625 - 128
01 3B 4 O2S8_WR_lambda(1):
Equivalence Ratio
Current		 0
-128		 2
128		 N/A
mA		 ((A*256)+B)*0.0000305
((C*256)+D)*0.00390625 - 128
01 3C 2 Catalyst Temperature
Bank 1, Sensor 1		 -40 6,513.5 °C ((A*256)+B)/10 - 40
01 3D 2 Catalyst Temperature
Bank 2, Sensor 1		 -40 6,513.5 °C ((A*256)+B)/10 - 40
01 3E 2 Catalyst Temperature
Bank 1, Sensor 2		 -40 6,513.5 °C ((A*256)+B)/10 - 40
01 3F 2 Catalyst Temperature
Bank 2, Sensor 2		 -40 6,513.5 °C ((A*256)+B)/10 - 40
01 40 4 PIDs supported 41-60 Bit encoded [A7..D0] == [PID 0x41..PID 0x60]
01 41 4 Monitor status this drive cycle Bit encoded. See below.
01 42 2 Control module voltage 0 65.535 V ((A*256)+B)/1000
01 43 2 Absolute load value 0 25,700  % ((A*256)+B)*100/255
01 44 2 Command equivalence ratio 0 2 N/A ((A*256)+B)*0.0000305
01 45 1 Relative throttle position 0 100  % A*100/255
01 46 1 Ambient air temperature -40 215 °C A-40
01 47 1 Absolute throttle position B 0 100  % A*100/255
01 48 1 Absolute throttle position C 0 100  % A*100/255
01 49 1 Accelerator pedal position D 0 100  % A*100/255
01 4A 1 Accelerator pedal position E 0 100  % A*100/255
01 4B 1 Accelerator pedal position F 0 100  % A*100/255
01 4C 1 Commanded throttle actuator 0 100  % A*100/255
01 4D 2 Time run with MIL on 0 65,535 minutes (A*256)+B
01 4E 2 Time since trouble codes cleared 0 65,535 minutes (A*256)+B
01 51 1 Fuel Type From fuel type table see below
01 52 1 Ethanol fuel % 0 100  % A*100/255
01 C3  ?  ?  ?  ?  ? Returns numerous data, including Drive Condition ID and Engine Speed*
01 C4  ?  ?  ?  ?  ? B5 is Engine Idle Request
B6 is Engine Stop Request*
02 02 2 Freeze frame trouble code BCD encoded, See below.
03 N/A n*6 Request trouble codes 3 codes per message frame, BCD encoded. See below.
04 N/A 0 Clear trouble codes / Malfunction indicator lamp (MIL) / Check engine light Clears all stored trouble codes and turns the MIL off.
05 0100 OBD Monitor IDs supported ($01 - $20)
05 0101 O2 Sensor Monitor Bank 1 Sensor 1 0.00 1.275 Volts 0.005 Rich to lean sensor threshold voltage
05 0102 O2 Sensor Monitor Bank 1 Sensor 2 0.00 1.275 Volts 0.005 Rich to lean sensor threshold voltage
05 0103 O2 Sensor Monitor Bank 1 Sensor 3 0.00 1.275 Volts 0.005 Rich to lean sensor threshold voltage
05 0104 O2 Sensor Monitor Bank 1 Sensor 4 0.00 1.275 Volts 0.005 Rich to lean sensor threshold voltage
05 0105 O2 Sensor Monitor Bank 2 Sensor 1 0.00 1.275 Volts 0.005 Rich to lean sensor threshold voltage
05 0106 O2 Sensor Monitor Bank 2 Sensor 2 0.00 1.275 Volts 0.005 Rich to lean sensor threshold voltage
05 0107 O2 Sensor Monitor Bank 2 Sensor 3 0.00 1.275 Volts 0.005 Rich to lean sensor threshold voltage
05 0108 O2 Sensor Monitor Bank 2 Sensor 4 0.00 1.275 Volts 0.005 Rich to lean sensor threshold voltage
05 0109 O2 Sensor Monitor Bank 3 Sensor 1 0.00 1.275 Volts 0.005 Rich to lean sensor threshold voltage
05 010A O2 Sensor Monitor Bank 3 Sensor 2 0.00 1.275 Volts 0.005 Rich to lean sensor threshold voltage
05 010B O2 Sensor Monitor Bank 3 Sensor 3 0.00 1.275 Volts 0.005 Rich to lean sensor threshold voltage
05 010C O2 Sensor Monitor Bank 3 Sensor 4 0.00 1.275 Volts 0.005 Rich to lean sensor threshold voltage
05 010D O2 Sensor Monitor Bank 4 Sensor 1 0.00 1.275 Volts 0.005 Rich to lean sensor threshold voltage
05 010E O2 Sensor Monitor Bank 4 Sensor 2 0.00 1.275 Volts 0.005 Rich to lean sensor threshold voltage
05 010F O2 Sensor Monitor Bank 4 Sensor 3 0.00 1.275 Volts 0.005 Rich to lean sensor threshold voltage
05 0110 O2 Sensor Monitor Bank 4 Sensor 4 0.00 1.275 Volts 0.005 Rich to lean sensor threshold voltage
05 0201 O2 Sensor Monitor Bank 1 Sensor 1 0.00 1.275 Volts 0.005 Lean to Rich sensor threshold voltage
05 0202 O2 Sensor Monitor Bank 1 Sensor 2 0.00 1.275 Volts 0.005 Lean to Rich sensor threshold voltage
05 0203 O2 Sensor Monitor Bank 1 Sensor 3 0.00 1.275 Volts 0.005 Lean to Rich sensor threshold voltage
05 0204 O2 Sensor Monitor Bank 1 Sensor 4 0.00 1.275 Volts 0.005 Lean to Rich sensor threshold voltage
05 0205 O2 Sensor Monitor Bank 2 Sensor 1 0.00 1.275 Volts 0.005 Lean to Rich sensor threshold voltage
05 0206 O2 Sensor Monitor Bank 2 Sensor 2 0.00 1.275 Volts 0.005 Lean to Rich sensor threshold voltage
05 0207 O2 Sensor Monitor Bank 2 Sensor 3 0.00 1.275 Volts 0.005 Lean to Rich sensor threshold voltage
05 0208 O2 Sensor Monitor Bank 2 Sensor 4 0.00 1.275 Volts 0.005 Lean to Rich sensor threshold voltage
05 0209 O2 Sensor Monitor Bank 3 Sensor 1 0.00 1.275 Volts 0.005 Lean to Rich sensor threshold voltage
05 020A O2 Sensor Monitor Bank 3 Sensor 2 0.00 1.275 Volts 0.005 Lean to Rich sensor threshold voltage
05 020B O2 Sensor Monitor Bank 3 Sensor 3 0.00 1.275 Volts 0.005 Lean to Rich sensor threshold voltage
05 020C O2 Sensor Monitor Bank 3 Sensor 4 0.00 1.275 Volts 0.005 Lean to Rich sensor threshold voltage
05 020D O2 Sensor Monitor Bank 4 Sensor 1 0.00 1.275 Volts 0.005 Lean to Rich sensor threshold voltage
05 020E O2 Sensor Monitor Bank 4 Sensor 2 0.00 1.275 Volts 0.005 Lean to Rich sensor threshold voltage
05 020F O2 Sensor Monitor Bank 4 Sensor 3 0.00 1.275 Volts 0.005 Lean to Rich sensor threshold voltage
05 0210 O2 Sensor Monitor Bank 4 Sensor 4 0.00 1.275 Volts 0.005 Lean to Rich sensor threshold voltage
09 02 5x5 Vehicle identification number (VIN) Returns 5 lines, A is line ordering flag, B-E ASCII coded VIN digits.

In the formula column, letters A, B, C, etc. represent the decimal equivalent of the first, second, third, etc. bytes of data. Where a (?) appears, contradictory or incomplete information was available. Someone with a copy of the 2006 SAE HS-3000 should fact-check these.

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:

Mode 1 PID 01: A request for this PID returns 4 bytes of data. The first byte contains two pieces of information. Bit A7 (the seventh bit of byte A, the first byte) indicates whether or not the MIL (check engine light) is illuminated. Bits A0 through A6 represent the number of diagnostic trouble codes currently flagged in the ECU. The second, third, and fourth bytes give information about the availability and completeness of certain on-board tests. Note that test availability signified by set (1) bit; completeness signified by reset (0) bit:

                 Test available      Test incomplete
Misfire                B0                   B4           
Fuel System            B1                   B5
Components             B2                   B6
Reserved               B3                   B7
Catalyst               C0                   D0
Heated Catalyst        C1                   D1
Evaporative System     C2                   D2
Secondary Air System   C3                   D3
A/C Refrigerant        C4                   D4
Oxygen Sensor          C5                   D5
Oxygen Sensor Heater   C6                   D6
EGR System             C7                   D7

Mode 1 PID 03: A request for this PID returns 2 bytes of data. The first byte describes fuel system #1. Only one bit should ever be set.

A0     Open loop due to insufficient engine temperature
A1     Closed loop, using oxygen sensor feedback to determine fuel mix
A2     Open loop due to engine load OR fuel cut due to desacceleration 
A3     Open loop due to system failure
A4     Closed loop, using at least one oxygen sensor but there is a fault in the feedback system
A5-A7  Always zero

The second byte describes fuel system #2 (if it exists) and is encoded identically to the first byte.

Mode 1 PID 12: A request for this PID returns a single byte of data which describes the secondary air status. Only one bit should ever be set.

A0     Upstream of catalytic converter
A1     Downstream of catalytic converter
A2     From the outside atmosphere or off
A3-A7  Always zero

Mode 1 PID 1C: A request for this PID returns a single byte of data which describes which OBD standards this ECU was designed to comply with. The hexadecimal and binary representations of the data byte are shown below next to what it implies:

0x01  00000001b    OBD-II as defined by the CARB
0x02  00000010b    OBD as defined by the EPA
0x03  00000011b    OBD ''and'' OBD-II
0x04  00000100b    OBD-I
0x05  00000101b    Not meant to comply with any OBD standard
0x06  00000110b    EOBD

Mode 1 PID 41: A request for this PID returns 4 bytes of data. The first byte is always zero. The second, third, and fourth bytes give information about the availability and completeness of certain on-board tests. Note that test availability signified by set (1) bit; completeness signified by reset (0) bit:

                  Test enabled       Test incomplete
Misfire                B0                   B4           
Fuel System            B1                   B5
Components             B2                   B6
Reserved               B3                   B7
Catalyst               C0                   D0
Heated Catalyst        C1                   D1
Evaporative System     C2                   D2
Secondary Air System   C3                   D3
A/C Refrigerant        C4                   D4
Oxygen Sensor          C5                   D5
Oxygen Sensor Heater   C6                   D6
EGR System             C7                   D7

Mode 3: (no PID required) A request for this mode returns information about the DTCs that have been set. The response will be an integer number of packets each containing 6 data bytes. Each trouble code requires 2 bytes to describe, so the number of packets returned will be the number of codes divided by three, rounded up. A trouble code can be decoded from each pair of data bytes. The first character in the trouble code is determined by the first two bits in the first byte:

A7 A6    First DTC character
-- --    -------------------
 0  0    P - Powertrain
 0  1    C - Chassis
 1  0    B - Body
 1  1    U - Network

As of September 2005, only P and U generic DTCs are standardized.


The second character in the DTC is a number defined by

A5 A4    Second DTC character
-- --    --------------------
 0  0    0
 0  1    1
 1  0    2
 1  1    3

The third character in the DTC is a number defined by

A3 A2 A1 A0    Third DTC character
-- -- -- --    -------------------
 0  0  0  0    0
 0  0  0  1    1     
 0  0  1  0    2
 0  0  1  1    3
 0  1  0  0    4
 0  1  0  1    5
 0  1  1  0    6
 0  1  1  1    7
 1  0  0  0    8
 1  0  0  1    9

The fourth and fifth characters are defined in the same way as the third, but using bits B7..B4 and B3..B0. The resulting five-character code should look something like "U0158" and can be looked up in a table of OBD-II DTCs.

Fuel Type Coding

Mode 1 PID 0x51 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

01    Gasoline
02    Methanol
03    Ethanol
04    Diesel
05    LPG
06    CNG
07    Propane
08    Electric
09    Bifuel running Gasoline
0A    Bifuel running Methanol
0B    Bifuel running Ethanol
0C    Bifuel running LPG
0D    Bifuel running CNG
0E    Bifuel running Prop
0F    Bifuel running Electricity
10    Bifuel mixed gas/electric
11    Hybrid gasoline
12    Hybrid Ethanol
13    Hybrid Diesel
14    Hybrid Eelctric
15    Hybrid Mixed fuel
16    Hybrid Regenerative

CAN Bus format

The PID query and response occurs on the vehicle's CAN Bus, using 3 particular CAN ids.

Query

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

Byte -> _ 0 _ _ 1 _ _ 2 _ _ 3 _ _ 4 _ _ 5 _ _ 6 _ _ 7 _
SAE Standard Number of
additional
data bytes:
2		 Mode
01 = show current data;
02 = freeze frame;
etc.		 PID code
(e.g.: 05 = Engine coolant temperature)		 not used
(may be 55h)
Vehicle specific Number of
additional
data bytes:
3		 Custom mode: (e.g.: 22 = enhanced data) PID code
(e.g.: 4980h)		 not used
(may be 00h or 55h)

Response

The vehicle responds to the PID query on the CAN bus with two messages, at IDs 7E8h and 7E9h. For standard (SAE) messages, the two messages are identical. For vehicle specific messages, they differ. Even though the number of bytes in the returned value is variable, the message uses 8 data bytes regardless. The bytes are:

Byte -> _ 0 _ _ 1 _ _ 2 _ _ 3 _ _ 4 _ _ 5 _ _ 6 _ _ 7 _
SAE Standard
7E8h and
7E9h or
7EAh		 Number of
additional
data bytes:
3 to 6		 Custom mode
Same as query, except that bit 6 is set. So:
41 = show current data;
42 = 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		 Number of
additional
data bytes:
3 to 6		 Custom mode: same as query, except that bits 5 and 6 are set.(e.g.: 62 = response to mode 22 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
7E9h		 Number of
additional
data bytes:
3		 7Fh Custom mode: (e.g.: 22 = enhanced diagnostic data) 31h not used
(may be 00h)

External links

  • OBD-Codes.com, detailed troubleshooting information on OBD-II codes
  • CAN Bus Vehicles, make, model and year vehicles that support OBD II CAN bus
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