ghost in the machine - wiring problems
08-25-2003, 05:34 PM
#1
Track Day
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Join Date: Jun 2002
Location: Evansville, In
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ghost in the machine - wiring problems
3 years ago I foolishly tried to replace my dead battery in near darkness. I got the leads crossed and got some nice sparks. Had it checked out but no "obvious" damage save a blown sunroof switch. However, since that time I have a periodic episode involving various warning lights including the ABD, ABS and other Warning Lights - similar to when first starting the car.
When it occurs, the engine will hesitate slightly (rpms drop) and there will be some popping noises through the sound system and then it goes away. This will go on for few days then not reappear for weeks. I have had it checked by both local dealer and my usual mechanic, neither of which have had any luck pin-pointing the problem through fault codes, etc.
Other symptoms" more prevalent in the morning after first starting the car, also seems to occur more when I have the AC on or when closing the sunroof. The interference in the sound system suggests a short of some kind but because it occurs so intermittently no one has been able to snuff it out.
Anyone have any suggestions? Is there some place where I can look over a wiring diagram to perhaps find some common strands btwn ac & sunroof?
When it occurs, the engine will hesitate slightly (rpms drop) and there will be some popping noises through the sound system and then it goes away. This will go on for few days then not reappear for weeks. I have had it checked by both local dealer and my usual mechanic, neither of which have had any luck pin-pointing the problem through fault codes, etc.
Other symptoms" more prevalent in the morning after first starting the car, also seems to occur more when I have the AC on or when closing the sunroof. The interference in the sound system suggests a short of some kind but because it occurs so intermittently no one has been able to snuff it out.
Anyone have any suggestions? Is there some place where I can look over a wiring diagram to perhaps find some common strands btwn ac & sunroof?
08-25-2003, 08:21 PM
#2
Rennlist Member
Hi,
Had a similar issue regarding "shorting the battery" when tightening the + ve terminal leads back onto a freshly charged battery using a wrench which touched the body work and cause a short.
Although I have not used the car much since I cannot say I have experienced the issues you talk off. I just checked the sunnroof and a/c and they seem to be working fine so I assume no fuses are blown.
I did notice some hesitation with idle after starting the car but I assume this is the ECU and ISV re learining their mapping....
Does anyone know if shorting the battery in such a way can cause any harm? I would have thought the car had fuses etc to prtect from these occurances? Any auto electricians out there?
<Macca
Had a similar issue regarding "shorting the battery" when tightening the + ve terminal leads back onto a freshly charged battery using a wrench which touched the body work and cause a short.
Although I have not used the car much since I cannot say I have experienced the issues you talk off. I just checked the sunnroof and a/c and they seem to be working fine so I assume no fuses are blown.
I did notice some hesitation with idle after starting the car but I assume this is the ECU and ISV re learining their mapping....
Does anyone know if shorting the battery in such a way can cause any harm? I would have thought the car had fuses etc to prtect from these occurances? Any auto electricians out there?
<Macca
04-26-2005, 08:23 PM
#3
5th Gear
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I know this is old, but it sure sounds like the same problem I'm having. I just bought a 97 C4S in January & the PPI did not turn up anything significant. However, if I use the power windows or sunroof when the radio & A/C are on I get a momentary loss of power (acceleration & electrical). The dash looks like a Christmas tree. The ABD & ABS lights come on, the radio goes off.. then everything goes back to normal. The car did have the battery replaced at the dealership long before I owned it. The only other problem I'm having is that the A/C blower makes a clicking noise when it's on low, like a flap is getting stuck. Not sure if that's related. Any help would be appreciated.