1986 328 - USA Car Thought I might elaborate on this issue with my car briefly mentioned in headlight thread. Read a few posts on this and did some digging of my own.... Symptoms: ALL door lights (red marker near door striker and white near door handle) have not worked for years. Interior dome light (interior rear view mirror area) as well, but only when trying to activate by opening door. Can rotate the dome switch to "always on" and dome light works. Note: Door buzzer works intermittently when you wiggle the door jam (hinge area, left/driver side) push switch. Testing: Drivers (left) side shows 12V current to both light sockets (red and white) at all times. So, as I have read on the 308s, the switch must control the ground, yes? Assume the passenger side is the same. Via experimentation, I was fiddling with the door jam switch on the passenger side and both door lights (red and white) came on for both doors (both doors were open). Dome light came on as well. When I close the pass. door, and leave the driver door open, everything goes out. Meaning, when I close the pass door and leave driver door open, when pass. switch is wiggled to work, the driver door and dome lights all go out. What I think I need: Pass side: Have a faulty door jam connection near / related to the switch that creates intermittent grounding. Driver Side: Assuming the jam switch for the door lights is not working AT ALL since wiggling does nothing and all goes out when pass door closes. No grounding happening at any time ever....? Also, since door buzzer only works when wiggling the lower switch, assume that ground is also acting up. I would like to think that all my issues relate to bad grounds near or at all three switches in the door jams? Is the 328 wiring the same in terms of the "side entry" of the wires to the rubber boot behind the switch? That seemed to be a problem for 308s? Any specific things to do or not do as I remove switched and possibly the plate the switches are mounted to...? Could this be as simple as fixing a loose ground wire behind each switch, assuming the switches work? Is there a source for replacement rubber switch covers? Sorry this rambled on..
I can't speak to Ferrari in particular but MANY others during that time period and earlier used the switch body to ground the lights. Take the jamb switch post, pull towards you and twist back and forth, if there is a little corrosion that may clear it right up. Or, it may come out in your hand which is also a good thing. There is generally one wire to the switch. If the switch comes out of the jamb just pull the wire off and ground it and look at the pretty lights. ;-)
Thanks... Yes, a friend of mine who was a Merc. Benz tech in the 80's told me to try the twist... So far, has not resolved, but will try again in case there is some buildup that I have not gotten so far... Drivers side, I got no indication of even intermittent success... But I think the problem is probably isolated to that area... the switches / grounds...
The wire at the back of the switch can flex until it breaks. I had an intermittent problem, as the wire would occasionally make contact. I soldered it back - a very long and delicate process, due to limited free wire. Pull the grommet out first.
Thanks. Im sure I'll find out more when I dig in.... 1. Does it make sense, if there is space to work, to splice in with a coupler (crimp) style connector some additional wire to provide length for current and future work? If it's just one wire to the switch? 2. Im not much on electrical knowledge, but thinking it through "on paper" can't get my head around why the driver door works when the pass. door ground failure is fixed... I'm thinking the driver side should have it's own ground and operate independently, but it appears that the pass. ground has an effect... And, failure of the driver side ground does not seem to alter the operation of the pass side...? Im just curious as to how it's all designed...
The design is such that either door will ground the circuit. Nothing special, just grounds. As to splicing in extra wire, well you could solder on a length of wire (I don't think there is enough room to get a crimp connector in there), cover it with shrink wrap and put the connector on the end but why? One fix and you're good for another 30 years or so.
