Note: This is basically a copy of the Audi S3 1.8T 2003 VAG PQ34 (ME 7.5) OEM CAN protocol, with some small changes to work on this vehicle.
NOTE: PDM20 uses the 0x50 CAN message ID for communication, which might be available on some Audi (equipped with airbag modules), do NOT use on the same bus!
Inputs.
•All four individual wheels speed from stock ABS into MaxxECU traction system.
•Engine oil pressure from instrument cluster, available in base tune.
Outputs.
•Instrument cluster (speed, tacho, CEL, odometer etc) working.
•Fuel consumption in instrument cluster.
Optional CAN.
•Stock ESP button can be used to activate/deactivate MaxxECU built in traction system, uses stock light on dash for confirmation.
Other support
•ABS is working
•Haldex AWD is working as OEM.
•Not working/issues.
•VCDS diagnostics with ECU is disabled.
Changelog
•Added cruise control buttons, using the OEM CAN Buttons.
•Added cruise control activation indication in dash.
•Added AC pressure from CAN.
•Output RPM changed from ENGINE RPM to TACHO RPM, to be used with the Tachometer output value presentation function as an option. (disable if any DSG control is activated, to prevent TCU error).
•Wheel speed correction function, engine considering running above 400rpm instead of 600rpm added/changed.
Added fuel consumption display in dash.
2020-02-27:
•Basetune available for download is now updated with Oil Pressure (from instrument cluster), if available.
•Smoother speedometer output in dash in.
Additional information
This CAN protocol has been tested with the following Audi models also:
•Audi S4 B5 (ECU number 8D0 907 551 D)
•Audi RS4 AZR (ECU number 8D0 907 551 K)
•Audi S4 (US spec), (ECU number 8D0 907 551M)
•Audi S4 (US spec), (ECU number 8D0 907 551A)
•Audi A4 (EU spec), (ECU number 8E0 909 518 AS/0261 208 500) <-- AC fan might not work, under investigation.
•VW MK4 Golf & Beetle (VR5 2.3 AQN.
•VW VR6 2.8 BDE.
Note: Audi S4 B5 must enable this protocol to get dash / abs to work properly, refers to ECUs ending with D,H,G,M.
Audi S3 dash
Arrow explanation
Green (light): Working.
Green (dark): Working (but not controlled by CAN).
Blue: Not ECU controlled.
Orange: Partly controlled by MaxxECU.
Yellow: Turned off.
Wheel circumference must always be calibrated using an OEM CAN protocol
When we calibrate the wheel speeds from an OEM vehicle (to make an OEM CAN Protocol), we always use the stock wheel sizes, so to get correct wheel speeds within MaxxECU, you must calibrate your wheel dimensions, since they are used to show you the correct speed in MaxxECU.
