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Haltech Help Needed

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I need help. I am having drive by wire issues on my new ECU in my E46 BMW (M54 motor). After about 2 hours of troubleshooting, it appears to be an internal issue with the ECU (or possibly with the firmware/software). We have verified the wiring in the attached picture from the throttle body (the image says M52, but it matches the BMW M54 wiring in the Bentley Service Manual). Our tune file is in Version 2.43.0 and the ECU Firmware is 2.43.0. Wiring references below are for people familiar with Haltech.

1. AVI3 is stuck at 4.2 volts. It does not move. We can swap the wires for TPS 1 and TPS 2 and AVI3 stays at 4.2V. We grounded AVI3 at the Haltech connector and it stays at 4.2V. Note that AVI2 works. When we swapped the wires on the engine harness and actuate the throttle by hand, we can see both TPS functioning correctly when read from AVI2. Additionally, you can see AVI2 floating around 4.2V, but not just rock solid at 4.2V like AVI3.

2. Fuel pump output turns on when we try to calibrate the DBW motor. We verified that DP05 is grounding in the Haltech connector from the ECU when we activate the DBW motor calibration.

3. The DBW motor output does nothing from the Haltech. When measuring voltage across the two wires, it goes from floating at about 0.030V to 0.000V when we try to calibrate.

4. We have extensively checked the wiring on the Haltech harness (including checking for short across pins and found no issues).This is a bit urgent as we have a race in 10 days and still need to start tuning.



Attached Files
  • M52_e-throttle.thumb.PNG.f43f0e3f1f91cda9dce7f1456acb1717.png
  • Attachments may only be downloaded by paid Gold members. Read more about becoming a Gold member here.

Send tune files so we can take look

You'll have to change the file extension from .mov to .e2500-243. It wouldn't let me attach the tune file or a .zip.

Attached Files

I've also just discovered that the CANbus connection on the harness is not functioning. The WB2 works when connected to the ECU, but there is no internal connection in the ECU when measured from the CANbus pin on the ECU side of the harness connector to the CANbus connection on the ECU.

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