Knowledgebase
OBD2 PIDs for Programmers (Technical)
Posted by Alex E. on 01 May 2018 09:03 PM

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, an automotive technician will use PIDs with a scan tool connected to the vehicle’s OBD-II connector.

  • The technician 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 technician

Modes

There are ten modes of operation described in the latest OBD-II standard SAE J1979. They are, the $ prefix indicating a hexadecimal number:

$01. Show current data

$02. Show freeze frame data

$03. Show stored Diagnostic Trouble Codes

$04. Clear Diagnostic Trouble Codes and stored values

$05. Test results, oxygen sensor monitoring (non CAN only)

$06. Test results, other component/system monitoring (Test results, oxygen sensor monitoring for CAN only)

$07. Show pending Diagnostic Trouble Codes (detected during current or last driving cycle)

$08. Control operation of on-board component/system

$09. Request vehicle information

$0A. Permanent DTC’s (Cleared DTC’s)

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).

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 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 [01 - 20]       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 absolute 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 ((A*256)+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

0-100(lean) 1.27599.2(rich) 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

0-100(lean) 1.27599.2(rich) 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

0-100(lean) 1.27599.2(rich) 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

0-100(lean) 1.27599.2(rich) 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

0-100(lean) 1.27599.2(rich) 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

0-100(lean) 1.27599.2(rich) 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

0-100(lean) 1.27599.2(rich) 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

0-100(lean) 1.27599.2(rich) 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) * 10) / 128
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

00 28 N/AV ((A*256)+B)/32768((C*256)+D)/8192
01 25 4 O2S2_WR_lambda(1):Equivalence Ratio

Voltage

00 28 N/AV ((A*256)+B)/32768((C*256)+D)/8192
01 26 4 O2S3_WR_lambda(1):Equivalence Ratio

Voltage

00 28 N/AV ((A*256)+B)/32768((C*256)+D)/8192
01 27 4 O2S4_WR_lambda(1):Equivalence Ratio

Voltage

00 28 N/AV ((A*256)+B)/32768((C*256)+D)/8192
01 28 4 O2S5_WR_lambda(1):Equivalence Ratio

Voltage

00 28 N/AV ((A*256)+B)/32768((C*256)+D)/8192
01 29 4 O2S6_WR_lambda(1):Equivalence Ratio

Voltage

00 28 N/AV ((A*256)+B)/32768((C*256)+D)/8192
01 2A 4 O2S7_WR_lambda(1):Equivalence Ratio

Voltage

00 28 N/AV ((A*256)+B)/32768((C*256)+D)/8192
01 2B 4 O2S8_WR_lambda(1):Equivalence Ratio

Voltage

00 28 N/AV ((A*256)+B)/32768((C*256)+D)/8192
01 2C 1 Commanded EGR 0 100 % 100*A/255
01 2D 1 EGR Error -100 99.22 % (A-128) * 100/128
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 (A is signed)
01 33 1 Barometric pressure 0 255 kPa (Absolute) A
01 34 4 O2S1_WR_lambda(1):Equivalence Ratio

Current

0-128 2128 N/AmA ((A*256)+B)/32768((C*256)+D)/256 – 128
01 35 4 O2S2_WR_lambda(1):Equivalence Ratio

Current

0-128 2128 N/AmA ((A*256)+B)/32768((C*256)+D)/256 – 128
01 36 4 O2S3_WR_lambda(1):Equivalence Ratio

Current

0-128 2128 N/AmA ((A*256)+B)/327685((C*256)+D)/256 – 128
01 37 4 O2S4_WR_lambda(1):Equivalence Ratio

Current

0-128 2128 N/AmA ((A*256)+B)/32768((C*256)+D)/256 – 128
01 38 4 O2S5_WR_lambda(1):Equivalence Ratio

Current

0-128 2128 N/AmA ((A*256)+B)/32768((C*256)+D)/256 – 128
01 39 4 O2S6_WR_lambda(1):Equivalence Ratio

Current

0-128 2128 N/AmA ((A*256)+B)/32768((C*256)+D)/256 – 128
01 3A 4 O2S7_WR_lambda(1):Equivalence Ratio

Current

0-128 2128 N/AmA ((A*256)+B)/32768((C*256)+D)/256 – 128
01 3B 4 O2S8_WR_lambda(1):Equivalence Ratio

Current

0-128 2128 N/AmA ((A*256)+B)/32768((C*256)+D)/256 – 128
01 3C 2 Catalyst TemperatureBank 1, Sensor 1 -40 6,513.5 °C ((A*256)+B)/10 – 40
01 3D 2 Catalyst TemperatureBank 2, Sensor 1 -40 6,513.5 °C ((A*256)+B)/10 – 40
01 3E 2 Catalyst TemperatureBank 1, Sensor 2 -40 6,513.5 °C ((A*256)+B)/10 – 40
01 3F 2 Catalyst TemperatureBank 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)/32768
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 53 2 Absoulute Evap system Vapour Pressure 0 327675 kpa 1/200 per bit
01 C3 ? ? ? ? ? Returns numerous data, including Drive Condition ID and Engine Speed*
01 C4 ? ? ? ? ? B5 is Engine Idle RequestB6 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 00 4 mode 9 supported PIDs 01 to 20       Bit encoded
09 02 5×5 Vehicle identification number (VIN)       Returns 5 lines, A is line ordering flag, B-E ASCII coded VIN digits.
09 04 varies calibration ID       Returns multiple lines, ASCII coded
09 06 4 calibration

 

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 eighth 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 deacceleration
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 (Europe)
0x07 00000111b EOBD and OBD-II
0x08 00001000b EOBD and OBD
0x09 00001001b EOBD, OBD and OBD II
0x0A 00001010b JOBD (Japan)
0x0B 00001011b JOBD and OBD II
0x0C 00001100b JOBD and EOBD
0x0D 00001101b JOBD, EOBD, and OBD II

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 0×51 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 Electric
15 Hybrid Mixed fuel
16 Hybrid Regenerative

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.

AutoEnginuity, who manufactures OBD-II scan tools, provides the following example on their website[1]:

Although Ford does implement the largest subset of the OBDII standard, the typical vehicle only supports 20 – 40 [standard] sensors and is limited to the emissions powertrain. Using the enhanced Ford interface, a typical Ford vehicle will support 200 – 300 sensors within half a dozen systems; that’s essential systems such as ABS, airbags, GEM, ICM, etc.

Our enhanced Ford interface coverage is only matched by factory tools; we have support for 3,400+ [Ford] sensors selected from all 58 [Ford] systems.

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 starts from US $7500[2]

However, even ETI membership will not provide full documentation for non-standard PIDs. ETI state[2]

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 of today’s per year charges as we know them:

GM $50,000

Honda $5,000

Suzuki $1,000

BMW $7,000 plus $1,000 per update. Updates occur every quarter. (This is more now, but do not have exact number)

CAN Bus format

The PID query and response occurs on the vehicle’s CAN Bus. Physical addressing uses particular CAN IDs for specific modules (e.g., 720 for the instrument cluster in Fords).

Functional addressing uses the CAN ID 7DFh, to which any module listening may respond.

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 -gt; _ 0 _ _ 1 _ _ 2 _ _ 3 _ _ 4 _ _ 5 _ _ 6 _ _ 7 _
SAE Standard Number ofadditional

data bytes:

2

Mode01 = show current data;

02 = freeze frame;

etc.

PID code(e.g.: 05 = Engine coolant temperature) not used(may be 55h)
Vehicle specific Number ofadditional

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 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.

The bytes are:

Byte -gt; _ 0 _ _ 1 _ _ 2 _ _ 3 _ _ 4 _ _ 5 _ _ 6 _ _ 7 _
SAE Standard7E8h,

7E9h,

7EAh,

etc.

Number ofadditional

data bytes:

3 to 6

Custom modeSame as query, except that 40h is added to the mode 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 specific7E8h, or 8h + physical ID of module. Number ofadditional

data bytes:

4to 7

Custom mode: same as query, except that 40h is added to the mode value.(e.g.: 62h = response to mode 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 specific7E8h, or 8h + physical ID of module. Number ofadditional

data bytes:

3

7Fh this a general response usually indicating the module doesn’t recognize the request. Custom mode: (e.g.: 22h = enhanced diagnostic data by PID, 21h = enhanced data by offset) 31h not used(may be 00h)
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