85fortheDrive

Ever since we've owned our 84, the tail light indicator warning light comes on as soon as I switch on the parking lights. All taillights are working.

I pulled the passenger side back side light and discovered that its wiring had been repaired by a PO. The repair uses an extra piece of wire to bridge a gap to the male end of the bulb receptacle.

I have heard tell that the car's means of knowing if a tail light is out is to find a resistance difference between the left and right sides of the car. Might this little extension wire cause this resistance differential?

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Backstory you may not be interested in...

Also, when we got the car, I noted that the ! light near the AC button was inverted. It looked like an "i" instead. I now think the PO got so tired of having the warning light come on each time he turned on his lights that he jerryrigged this button to always be depressed. Now that I've returned it to its proper orientation, it dutifully comes on each time I turn on the lights.

So I'm guessing this tail light warning has been going on for a long time.

Thanks folks.

Tim

Big Dave

Are both of your license plate lights functioning? Just checking...

Alan

The "!" button front for the switch works exactly the same either way up - likely there was a connection issue if it now works and didn't before.

The test for the lights measures the voltage drop across a deliberate resistance in the bulb control unit. This wire would only affect that if its a very small guage - just replace with a beefy version if you have any doubts - I suspect it is not the cause of your problems.

Change out all the bulbs for correct fresh versions and look to see they all appear to be the same brightness - if any look dim - check connections (clean etc).

Alan

AO

+1

928drvr86.5

Probably a high resistance connection somewhere.

85fortheDrive

Good call there, Dave and Andrew. I looked last week and they were both on, but will check again. I can see how these would be overlooked.

Yep. But along with accidentally flipping it, the PO sandwiched the button mechanism so that it was always depressed and therefore didn't light up.

Ah, homework! Glad to do it. Thanks for this suggestion, Alan.
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