carbarrco

Hello,

I went to replace my ignition switch only to find that the back of the OEM switch had melted in one location. The harness was also melted along with a portion of red wire leading to the panel.

my headlights do not work and my car will not start (1998 a4 2.8 quattro) I have replaced several items and cannot seem to resolve the no-start condition. But my question is : what could have caused the wire to melt? I believe it's the 30 A red wire.

carbarrco

I did not realize this was going to be a post.. My apologies.


My b5 a4 suddenly stopped working one morning when it was approximately -30* F. I tried to start the car and it just turned over. The battery was old so I replaced it immediately. Still no start.

I checked for spark, Good.
Fuel Pump, Good.
Air filter, Dirty - replaced it.
Inspected timing belt, felt okay and looked in tact.
Starter was strong (600-800+ rpm)

[At this point my engine codes are for the failed SAI but whatever. I live in an emissions-testing-free county. ]

after a few more days of messing around the battery died out and I had to jump the car.

Stopped hearing the fuel pump prime so I replaced it and the fuel pump relay.
I installed new spark plugs.
Still jumping the car with no success.

Previous owner had a new ICM in the car for when the time came... So I went ahead and installed it
Unbeknownst to me, had a bad wire (positive) touching the BODY OF THE ICM.
Short to ground Codes were thrown for the following:

https://goo.gl/photos/sd5rP9mQPGkwE9LLA
https://goo.gl/photos/o7XyrXHzquFF8ZP26
(SAI, Evap Purge, Intake Manifold, Evap Leak, and all 6 fuel injectors threw short to ground)

I went to replace the ignition switch and realized the back of it had burned ( red wire that I've seen on other threads) I went ahead with the installation (adding electrical tape to an exposed piece of that red wire ) Jumped the car, it cranked, but no start.

Now my starter sounds weak on top of all this.

Can anyone offer some beta for approaching this electrical nightmare? I found a hack for the red wire and may pursue that route unless someone else has a better idea?

carbarrco

David.Norton

Can't help but wonder if you are not dealing with two issues. The burned wire on the back of the switch was likely caused by a bad switch, the connections get poor and then overheat. Over time things can get pretty cooked. As far as the short on the battery lead on the ECU (I hope you are referring to the ECU, not sure what the ICM refers to) the battery line is unfused, and I suspect a fusable link in the harness has burned. I would check and see if the battery lead on the ECU has power, if not you have an open in the harness, otherwise I would be just guessing.

carbarrco

still dealing with this no-start issue..

I scanned again and cylinders 1-6 are showing open circuit. SAI and evap purge are short to ground as well as my intake manifold.

low voltage terminal 30: voltage too low intermittent.

I was able to force my fuel pump to work and checked the line..it's good.
I have spark in all 6.

Has anyone here dealt with a similar scenario? I am looking for suggestions on where to look. The ECM seems okay, no burnt leads or cables. I suspect a bad ground may be causing my troubles but nothing seems obviously damaged to me. *fuel pump relay is new* fuel injection relay is being replaced in hope of resolving this. although, the old one seemed to function just fine and had no visible damage.

There's a gremlin in my wiring I'm not seeing...any help is appreciated!