1977 Electrical Problem
Thread Starter
Instructor
Joined: Jan 2011
Posts: 221
Likes: 1
From: Sylmar CA
1977 Electrical Problem
I just replaced all the fuses and bulbs on my car. Everything was working fine with the key open and the car off. I start the car up and as soon as I do my turn signals don't work anymore and when I step on the brakes, the left rear light won't turn on. Anyone have any ideas why?
Also this 'GEN' light keeps flickering on and off in my car, anyone know what it is, what it means, if its supposed to be on or off and how I can fix this?
Also this 'GEN' light keeps flickering on and off in my car, anyone know what it is, what it means, if its supposed to be on or off and how I can fix this?
Melting Slicks
Joined: Jul 2005
Posts: 2,740
Likes: 3
From: Aurora Ontario
Did you have a problem before you changed the fuses? You may have activated a circuit with the new fuse that was a pre-existing problem.
You may have installed the wrong bulb somewhere. Start by pulling the one that does not work, left rear.
I see in the pic of your guage the volts are well below 13, that could also cause the GEN light to flicker. When you give it gas do the Volts climb....they should.
Jim
You may have installed the wrong bulb somewhere. Start by pulling the one that does not work, left rear.
I see in the pic of your guage the volts are well below 13, that could also cause the GEN light to flicker. When you give it gas do the Volts climb....they should.
Jim
Instructor
Joined: Jan 2006
Posts: 228
Likes: 1
From: Warwick New York
I would check the grounds both in the back by the lights themselves and in the front near the alternator. It seems that the lights are useing a source to ground that is taken away when you start the car. Sound like you have your work cut out for you. good luck
Thread Starter
Instructor
Joined: Jan 2011
Posts: 221
Likes: 1
From: Sylmar CA
Jim, yeah the problem existed before I changed the fuses, that's why I changed them to see if it would fix the problem.
Also the bulbs all work because when the car is off but the key is turned, all the lights work sometimes, and sometimes the left rear stop light won't work. Although the tail light works. It works sometimes and sometimes it doesn't. Same goes for the turn signals. And I don't know why this is happening.
And in the picture its with the car off at 12 volts. With the car on its at around like 15 volts approximately.
captl27, how do I check the ground in the back lights? Is it coming straight from the bulb or how?
Also the bulbs all work because when the car is off but the key is turned, all the lights work sometimes, and sometimes the left rear stop light won't work. Although the tail light works. It works sometimes and sometimes it doesn't. Same goes for the turn signals. And I don't know why this is happening.
And in the picture its with the car off at 12 volts. With the car on its at around like 15 volts approximately.
captl27, how do I check the ground in the back lights? Is it coming straight from the bulb or how?
Instructor
Joined: Jan 2006
Posts: 228
Likes: 1
From: Warwick New York
The grounds are throughout the car. you should see screws with wires bolted to the metal parts in the rear bumper section of the car. A test light with and extra long lead clamped to the the positive pole of the battery can help test these problems. If you have your test light hooked to the positive terminal and you touch it to the metal part of the light socket it should light no mater where the ignition switch is.
Last edited by captl27; Jan 16, 2012 at 09:23 AM.
Melting Slicks
Joined: Jul 2005
Posts: 2,740
Likes: 3
From: Aurora Ontario
Jim, yeah the problem existed before I changed the fuses, that's why I changed them to see if it would fix the problem.
Also the bulbs all work because when the car is off but the key is turned, all the lights work sometimes, and sometimes the left rear stop light won't work. Although the tail light works. It works sometimes and sometimes it doesn't. Same goes for the turn signals. And I don't know why this is happening.
And in the picture its with the car off at 12 volts. With the car on its at around like 15 volts approximately.
captl27, how do I check the ground in the back lights? Is it coming straight from the bulb or how?
Also the bulbs all work because when the car is off but the key is turned, all the lights work sometimes, and sometimes the left rear stop light won't work. Although the tail light works. It works sometimes and sometimes it doesn't. Same goes for the turn signals. And I don't know why this is happening.
And in the picture its with the car off at 12 volts. With the car on its at around like 15 volts approximately.
captl27, how do I check the ground in the back lights? Is it coming straight from the bulb or how?
I am not familiar with 77 fuse system. First turn everything off like the radio.
Pull a fuse and start the car. See if the gen light stops flickering. If the pulled fuse dosen't do it put it back in and pull another and keep repeating the proces until you find the one that eliminates the gen flash.
As each fuse is pulled go out and eyebal the lights and see if there is a change in how bright they are.
Its process of elimination.
Thread Starter
Instructor
Joined: Jan 2011
Posts: 221
Likes: 1
From: Sylmar CA
The fuses seem to temporarily fix the problem. I pull them and put in the ones for the stop and taillights. Pop them back in(still working) and the lights all work, except interior dash lights. And then while driving they die again. I have been meaning to check it out but its been raining here so I haven't had a chance to check the electrical outside.
Another thing the step lights and the light by the t tops came on and stay on, no matter what. It happened when I was trying to pull the circuit breaker to replace it in the fuse box. Battery was still hooked up. Then I smelled some smoke coming from under the hood near the fuse box area. Since then the lights have stayed on and I don't know why. I popped out the fuse to keep my battery from dying and keep the lights off. Any ideas?
And I figured out the 'GEN' light problem. Some wires were loose on my alternator. I rewired it and hooked it up and the light is off now
I'll check the grounds when its not raining outside anymore lol
Another thing the step lights and the light by the t tops came on and stay on, no matter what. It happened when I was trying to pull the circuit breaker to replace it in the fuse box. Battery was still hooked up. Then I smelled some smoke coming from under the hood near the fuse box area. Since then the lights have stayed on and I don't know why. I popped out the fuse to keep my battery from dying and keep the lights off. Any ideas?
And I figured out the 'GEN' light problem. Some wires were loose on my alternator. I rewired it and hooked it up and the light is off now
I'll check the grounds when its not raining outside anymore lol
Melting Slicks
Joined: Jul 2005
Posts: 2,740
Likes: 3
From: Aurora Ontario
The fuses seem to temporarily fix the problem. I pull them and put in the ones for the stop and taillights. Pop them back in(still working) and the lights all work, except interior dash lights. And then while driving they die again. I have been meaning to check it out but its been raining here so I haven't had a chance to check the electrical outside.
Another thing the step lights and the light by the t tops came on and stay on, no matter what. It happened when I was trying to pull the circuit breaker to replace it in the fuse box. Battery was still hooked up. Then I smelled some smoke coming from under the hood near the fuse box area. Since then the lights have stayed on and I don't know why. I popped out the fuse to keep my battery from dying and keep the lights off. Any ideas?
And I figured out the 'GEN' light problem. Some wires were loose on my alternator. I rewired it and hooked it up and the light is off now
I'll check the grounds when its not raining outside anymore lol
Another thing the step lights and the light by the t tops came on and stay on, no matter what. It happened when I was trying to pull the circuit breaker to replace it in the fuse box. Battery was still hooked up. Then I smelled some smoke coming from under the hood near the fuse box area. Since then the lights have stayed on and I don't know why. I popped out the fuse to keep my battery from dying and keep the lights off. Any ideas?
And I figured out the 'GEN' light problem. Some wires were loose on my alternator. I rewired it and hooked it up and the light is off now
I'll check the grounds when its not raining outside anymore lol
I would disconnect the battery and remove the fuse block. Unfortunately I dont' know how to do this on a 77. There will be a big plug back there. You need to get at it.
Jim
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