My brother has an 87 Buick regal with an olds 307 and none of the courtesy lights come on.

The fuse is blown obviously so I replaced it. And I noticed that as soon as I replaced it, the engine compartment light blew then shortly after came the fuse. This light is part of the circuit.

I have an inkling that this is my problem, if I remember when I took my physics class we learned about circuits and I remember learning that if say a light bulb were to short out then the circuit it incomplete.

Do you guys think that the problem is just the bulb, or is it something deeper. I haven't checked the circuit with my multimeter yet, and I plan to do it soon.

 

A light bulb is a controlled short. If you are replacing the fuse with the proper amp rating and it blows, what you probably have is a short in the positive wire some where in the circuit causing the fuse to blow.

 

positive wire as in the power cable?

 

Oh OK I see what you're talking about.

 

Well by looking at this, theoretically, if the engine bay light blows won't there be excessive power in the circuit therefore overloading the fuse?

 

Lights only draw what they draw. Having less lights active will not blow a fuse. A short to ground will blow a fuse.

 

Oh Okay that makes sense, that isolates the problem to the courtesy section of the light switch and onwards since the headlights, parking lights, tail lights are functioning properly. I should look at the junction block and check for continuity.

 

If you are blowing a 20A fuse, you have a short somewhere in the orange wires to the cig lighter, clock, courtesy lights, engine comp. light, or glove box light. Since the engine comp light lights and goes out with the fuse blowing, I would say your problem is not there. If the courtesy lights briefly light also until the fuse blows, I might rule them out also. Chances are the short is in the cig lighter, remove the heavy wire at the back of the socket (it should just pull off) and replace the fuse, if it blows the issue is somewhere else.

 

Yeah that's what I was thinking, I read that the g bodies have weird wiring and that the cig lighter is a culprit. I noticed that this one is a new one when I took the center console apart. It wasn't the original part which gives me the suspicion that the previous owners had this problem. I might just end up removing it and taping off the connection with electrical tape. My brother's not a smoker.

 

Bump!

Any particular way to remove the cigarette lighter? Pulling out the AC controls gives me access to the back of it. How does the thing go out?
​​​​threaded?

 

The lighter itself or the socket? Can you just reach the wire thats plugged on the back and disconnect it for your testing instead of removing the whole unit.

 

Yes, I found that to be the problem. I am talking about the lighter itself.

 

It just pulls out.

 

Thank you very much!