CAN Bus database

CAN bus mappings by OEM ECU and aftermarket device

Megasquirt CAN ( MS2/MS3/MS3 Pro )

Installation instructions

• Baud Rate: 1MB (Configurable in Megasquirt)
• Values in big endian format
• Default base CAN id: 1520
• Full CAN bus mapping for Megasquirt

Megasquirt CAN
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

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

MBE Systems 992 (Locked Caterham mode)

Installation instructions

• Baud Rate: 500K

MBE Systems 992
Channel	Units	CAN Id	Offset (bytes)	Length (bytes)	Conversion	Notes