I've got a pretty nice 1993 CB9, manual transmission with a straight no-rust body, it's still rocking all it's OEM parts or at least OEM style and has no modifications, even the original radio is there. Since the day I got it about two years ago, it's told me the driver's door, both rear passenger doors, and the liftgate are open. The front passenger door is always shown closed (I suspect the dashboard light is burnt out for that door). The dome light doesn't come on at all, and the door chime never sounds. This is probably a good thing, they'd quickly become annoying while tooling down the road.
This car leaked everything when I got it, it leaked so much from so many places I couldn't even tell where all the leaks where, but when I fixed the leak at the distributor (which was soaking down the engine wire harness), the door behavior began to change.
The behavior change also started when it was really cold out, ambient temperatures below freezing would often see the door indicator lights working correctly upon starting the car. This would last for a little while, with the indicator lights slowly brightening up. During that time, the door indicator lights would correctly indicate a door was open or closed (except that passenger front door, it's always indicated closed). Even the lift-gate indicator would work properly. To date, this change in behavior has become more common. Sometimes even happening in warm weather up to 70 degrees, but the lights will always come one within 10 minutes or so.
I've gone through all the regular door switches, they all operate normally and test fine with a continuity tester. I don't know how the lift-back switch works exactly, but I've fiddled with it as well. Disconnecting it does nothing to change behavior. The only behavior change I've been able to elicit consistently is with temperature. The lights are just more likely to work properly when it's really cold out, and slowly come back to the failure mode with vehicle operation.
I can do just about anything mechanically, I've already torn this poor car's engine all apart in a quest to fix oil leaks, a head gasket failure, coolant leaks, a timing belt and waterpump change. I'm not super smart about electrical, but I can read simple electrical diagrams and identify components pretty well. My thought was that there was likely a bad diode somewhere, as a proper diode allows current one way but not the other (backfeeding), and I thought a diode would be more likely to function properly when cold, and fail when hot, and I thought maybe just maybe something was backfeeding the door switch circuit grounds, thus causing the lights to illuminate. So if anyone knows anything that uses a common ground with the door light circuits, that would be a likely candidate for further investigation.
I'm also will to take a totally different approach. Like I said, I'm not really great with electrical. I know some theory, but combined with little practical knowledge I think I'm more likely to do something stupid.
This car leaked everything when I got it, it leaked so much from so many places I couldn't even tell where all the leaks where, but when I fixed the leak at the distributor (which was soaking down the engine wire harness), the door behavior began to change.
The behavior change also started when it was really cold out, ambient temperatures below freezing would often see the door indicator lights working correctly upon starting the car. This would last for a little while, with the indicator lights slowly brightening up. During that time, the door indicator lights would correctly indicate a door was open or closed (except that passenger front door, it's always indicated closed). Even the lift-gate indicator would work properly. To date, this change in behavior has become more common. Sometimes even happening in warm weather up to 70 degrees, but the lights will always come one within 10 minutes or so.
I've gone through all the regular door switches, they all operate normally and test fine with a continuity tester. I don't know how the lift-back switch works exactly, but I've fiddled with it as well. Disconnecting it does nothing to change behavior. The only behavior change I've been able to elicit consistently is with temperature. The lights are just more likely to work properly when it's really cold out, and slowly come back to the failure mode with vehicle operation.
I can do just about anything mechanically, I've already torn this poor car's engine all apart in a quest to fix oil leaks, a head gasket failure, coolant leaks, a timing belt and waterpump change. I'm not super smart about electrical, but I can read simple electrical diagrams and identify components pretty well. My thought was that there was likely a bad diode somewhere, as a proper diode allows current one way but not the other (backfeeding), and I thought a diode would be more likely to function properly when cold, and fail when hot, and I thought maybe just maybe something was backfeeding the door switch circuit grounds, thus causing the lights to illuminate. So if anyone knows anything that uses a common ground with the door light circuits, that would be a likely candidate for further investigation.
I'm also will to take a totally different approach. Like I said, I'm not really great with electrical. I know some theory, but combined with little practical knowledge I think I'm more likely to do something stupid.
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