Motronic Problems
#1
Motronic Problems
I am having trouble with the ecu in my Urs6 Avant. It had been chipped By MTM when I bought it. One morning It would not start. I checked it for the usual engine stuff, fuel, spark and air... It was not getting spark to the coils. I loaded it up and hauled it to my local German guy. He determined these things: Checked for spark and injector signal. No signal from Motronic control unit(ECU). Checked for B+ from main relay. Main relay is not sending power. Found main relay is built into ECU. Checked for power signal from fuse 104, Good check, grounds to ECU. Internal main relay is not working. Also Checked fuel pressure OK at 48psi. I sent the ECU off to have a new chip burnt and installed on the main board of the ECU. The man who did the work tested it by plugging it into his 94' URS4. It worked fine after the chip fix. He mailed it back and I plugged it in. The entire interior with exception of the dash is removed right now while I Have a new carpet kit manufactured so all the wiring is exposed. The car ran fine until I had plugged in the hazard relay/seat heater switch bank, my aftermarket stereo head unit and climate controls. When I Tried to start the car the ECU was dead again. My question is what in the dash wiring could be causing the problem? I am stumped. Any knowledge would be appreciated.
#3
Who did you send the ECU to be fixed? (That relay inside the ECU is called the holding relay and has zero to do with the chips. The MTM chips were probably fine).
Things to read:
Holding relay info
Potential reasons why your AAN is not starting
My AAN didn't start yesterday because the battery is low and it couldn't spin the engine up to 13 RPM during start. Need to put the battery on a charger.
Things to read:
Holding relay info
Potential reasons why your AAN is not starting
My AAN didn't start yesterday because the battery is low and it couldn't spin the engine up to 13 RPM during start. Need to put the battery on a charger.
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