CAN Bus database

CAN bus mappings by OEM ECU and aftermarket device

Motec M84

  • Standard Channel Mapping for Motec M84 ECU
  • Big Endian (MSB) data format
Motec M84
Channel Units CAN Id Offset (bytes) Length (bytes) Multiplier Adder Notes
RPM RPM ? 0 2 1 0
TPS % ? 2 2 1 0
MAP kPa ? 4 2 1 0
AIT C ? 6 2 1 0
EngineTemp C ? 8 2 1 0
AFR Lambda ? 10 2 1 0
FuelPress kPa ? 20 2 1 0
OilPress kPa ? 24 2 1 0
Speed? (Dig In 1 Speed?) ? 52 2 1 0 Need to verify this field
InjDutyCyc % ? 110 2 1 0


AIM Smarty CAM CAN protocol

Installation instructions

  • Baud Rate: 1MB
  • Values in little endian format
AIM Smarty CAM protocol
Channel Units CAN Id Offset (bytes) Length (bytes) Multiplier Adder Notes
RPM RPM 1056 0 2 1 0
EngineTemp C 1056 6 2 0.1 0
OilTemp C 1057 4 2 0.1 0
OilPress Bar 1057 6 2 0.01 0
TPS % 1058 2 1 1 0
Fuel L 1070 0 1 1 0

Megasquirt CAN ( MS2/MS3/MS3 Pro )

Installation instructions

Megasquirt CAN (Dashboard Mode)
Channel Units CAN Id Offset (bytes) Length (bytes) Conversion Notes
In development


Megasquirt CAN (standard mode)
Channel Units CAN Id Offset (bytes) Length (bytes) Conversion Notes
RPM RPM 1520 6 2 (B6 * 256) + B7
IgnTiming Degrees 1521 0 2 ((B0 * 256) + B1) / 10
AFR AFR 1521 4 2 ((B4 * 256) + B5) / 10 Legacy AFR1 (Deprecated on MS3) - to use AFR2 specify offset 6
MAP kPa 1522 2 2 ((B2 * 256) + B3) / 10
MAT F 1522 4 2 ((B4 * 256) + B5) / 10
EngineTemp F 1522 6 2 ((B6 * 256) + B7) / 10
TPS % 1523 0 2 ((B0 * 256) + B1) / 10
EngineTemp F 1522 6 2 ((B6 * 256) + B7) / 10
Knock % 1524 0 2 ((B0 * 256) + B1) / 10 Indication of knock input
AFR % 1551 0 1 B0 / 10 AFR for cylinder #1 (MS3+ compatible) - add 1 to offset for subsequent AFR inputs

BMW E46

Installation instructions

  • Baud Rate: 500K
  • Little Endian Format
BMW E46 (including M3)
Channel Units CAN Id Offset (bytes) Length (bytes) Conversion Notes
TPS % 809 6 1 (B6 / 255)
EngineTemp C 809 2 1 (B2 * 0.75) - 48.373 Convert to Farenheight: (temperatureC * 1.8) + 32
OilTemp C 1349 5 1 B5 - 48.373 Convert to Farenheight: (temperatureC * 1.8) + 32
RPM 790 3-4 1 ((B4 * 256) + B3) / 6.4

Mini Cooper R53

Installation instructions

  • Baud Rate: 500K
  • Little Endian Format
Mini Cooper R53
Channel Units CAN Id Offset (bytes) Length (bytes) Conversion Notes
TPS % 809 6 1 (B6 / 254) * 100
EngineTemp C 809 2 1 (B2 * 0.75) - 48.373 Convert to Farenheight: (temperatureC * 1.8) + 32
RPM 790 3-4 1 ((B4 * 256) + B3) / 6.4

MBE Systems 992

Installation instructions

  • Baud Rate: ???
  • Little Endian format
MBE Systems 992 (Locked Caterham mode)
Channel Units CAN Id Offset (bytes) Length (bytes) Conversion Notes
EngineTemp C? 814 0 1 B0 Need to verify scaling and temperature units
RPM RPM 814 1 2 (B2 * 256) + B1
TPS % 814 3 0 B0 / 5.0 Outputs as throttle voltage. assuming a 0-5v system, scale by 5v
OilPress PSI? 815 2 1 B2 Need to verify scaling and Pressure units
OilTemp C? 815 3 1 B3 Need to verify scaling and temperature units

Brightwater Technologies

Brightwater TPMS
Channel Units CAN Id Offset (bytes) Length (bytes) Multiplier Adder Notes
TirePres_RF PSI 1440 2 2 0 0.01
TireITmp_RF C 1440 3 1 -40 0 Internal Tire Temperature
TirePres_LF PSI 1441 2 2 0 0.01
TireITmp_FL C 1441 3 1 -40 0 Internal Tire Temperature
TirePres_RR PSI 1442 2 2 0 0.01
TireITmp_RR C 1442 3 1 -40 0 Internal Tire Temperature
TirePres_RL PSI 1443 2 2 0 0.01
TireITmp_RL C 1443 3 1 -40 0 Internal Tire Temperature