wiring woes
06-04-2007, 03:56 PM
#1
Instructor
Thread Starter
wiring woes
A few weeks ago, on my '89 S4 (auto), the "door-is-ajar" warning began to chime continuously and the interior lights wouldn't turn off, while the car was running.
Since I had recently replaced the rear hatch receiver I figured that was the first place to start looking for the cause. But everything there checked out okay. Eventually I did discover a problem, the interior light switch (inside the passenger's door jamb) was shot. It had come apart, the nipple and inner spring were gone, missing entirely.
Okay, no big deal I thought to myself, order a new switch, remove what's left of the old one, transfer the wire, thread it back into the door jamb and within a few minutes I'll be done, right? WRONG!
When I removed the old switch I found only frayed strands of wire connected to the switch. Aw nuts! After locating where the wire enters the door frame and inspecting the wire I found that it has deteriorated terribly. The outer coating seems to have decomposed or melted away, and the exposed wire is brittle and flat grey in color. I've been unwrapping the section of harness this wire feeds from and so far it appears the entire wire is in this condition. Yet all of the surrounding wires appear to be fine.
Anyone know what the heck would cause this?
Jeff
Since I had recently replaced the rear hatch receiver I figured that was the first place to start looking for the cause. But everything there checked out okay. Eventually I did discover a problem, the interior light switch (inside the passenger's door jamb) was shot. It had come apart, the nipple and inner spring were gone, missing entirely.
Okay, no big deal I thought to myself, order a new switch, remove what's left of the old one, transfer the wire, thread it back into the door jamb and within a few minutes I'll be done, right? WRONG!
When I removed the old switch I found only frayed strands of wire connected to the switch. Aw nuts! After locating where the wire enters the door frame and inspecting the wire I found that it has deteriorated terribly. The outer coating seems to have decomposed or melted away, and the exposed wire is brittle and flat grey in color. I've been unwrapping the section of harness this wire feeds from and so far it appears the entire wire is in this condition. Yet all of the surrounding wires appear to be fine.
Anyone know what the heck would cause this?
Jeff
06-04-2007, 08:24 PM
#3
Team Owner
the wire your unwrapping is a ground wire for the door switch trace back to a good wire and run a new one also look for possible shorts, the door switch probably let got due to heating of the post. This job is kind of a pain but you should find the bad wire
06-04-2007, 11:20 PM
#6
Instructor
Thread Starter
Dave thanks for that reminder. Very good advice. I wouldn't have suspected the fuses since I haven't needed to replace any of them since taking ownership five years ago. Hmmmmm... Then too, there have been three POs before me, and who knows how many marginal mechanics. All the more reason to be double checking every single one of them!!!