Car normally runs fine. I tryed to start it and it just keeps turning over. Get the VAG COM out to see whats going on and I cant connect to the ECM. I can connect to all other modules but just not the ECM.
Check fuel pump since I did not hear that coming on and I am only getting 3.5 volts at the pump. Battery seems to be good as the car turns over as expected.

Any Ideas... does the ECM control the fuel pump, maybe the ECM died?

Are there some relays I should test or jumper.

thanks,
-platinum

 

i checked the voltage at the fuse panal for the fuel pump and it is 3.5v there as well.

I also have no voltage at fuse 32 - control unit engine.

what supplies power to fuse 32?

 

what year is it...?

and can you talk w/ the abs control module.... brake electronics....?

 

2000 A4 1.8T

yes, I can connect to all other modules. I also tried disconnected the ABS since I guess that is a common problem when communicating to the ECU.

 

i think next i would try a fuel volume test. exact measurement isn't necessary.... just looking for either a little or alot.

the voltage at the fuel pump can be misleading.... cause i don't think its supposed to be 12v.

 

There is zero fuel, the pump does not come on but either does the ECM.

its gotta be the igition switch, relay or something.

 

Just replace the ignition switch and the J17 (fuel/ecu) relay and same issue. I still do not have power at fuses 32/24. What else could this be.

please help!!!

 

dont know if this helps.

here are the voltages at the fuel relay

I have the following on the relay

30, T, 86, 87a, 87. labeled on relay. Those corispond to 20, 18, 19, 17, 23 where it plugs in. below are the votages with the key in the on position.

relay/plug--voltage

30/20 -- 1.7v

T/18 -- 12v

86/19 -- 3.49

87a/17 --12v

87/23 --0v

 

I would really like to know the cause of this, I have the same probem. No power to the pump.. Fuse is good, I also changed out the relay... still no power to the pump.

 

Still working the issue on my end. Not getting much help though. The local dealership has a car in there right now with the same issue that they have not been able to figure out for over 6 weeks.

I will keep you posted if I figure it out.