79 with strange electrical issue
Thread Starter
Cruising
Joined: Sep 2015
Posts: 10
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79 with strange electrical issue
I am getting a draw on my battery on my 79. That battery goes dead pretty much overnight. My gauges(volt meter) are reading even with the key out. If I pull the fuse for the gauges I loose the draw. I used the test light method to confirm this. I have replaced the ignition switch to no avail. Another strange thin is my brake light(the one in the center of the cluster) comes on when I am cranking the engine. I have put in a battery disconnect , but I would like to fix this properly as I have gave my vette to my daughter and I don’t want her to have to deal with that issue. Any ideas where to look would be great. Thanks, in advance.
Jason
Jason
Pro
Joined: Nov 2016
Posts: 729
Likes: 118
From: Kelowna British Columbia
When you pulled your fuses and lost it you should have put back 1 at a time until the draw came back and that identifies the circuit drawing current. Then with wiring diagram you can start opening this circuit to find trouble
Melting Slicks
Joined: Feb 2007
Posts: 2,709
Likes: 269
From: S.E. MI
St. Jude Donor '15
I would look at the back of the gauge panel. The traces can come loose on the pcb where the main connector plugs in or other places. Just have to super glue them down if they are loose.
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Thread Starter
Cruising
Joined: Sep 2015
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So I removed my radio, disconnected the alternator, and the courtesy light timer has been removed, and I still have a draw. I pulled the center gauges out and once disconnected the draw is gone. I have constant power to the orange wire (the clock) and the pink wire which if I am reading the wiring diagram right goes to the seat belt/ key warning buzzer and the gauges fuse. Is that circuit supposed to have constant power? I have 2 79s and my other one doesn’t have power to the gauges with the key off. I am also still trying to figure out why my brake light comes on when cranking over also. Any suggestions?
Jason
Jason
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Joined: Dec 2006
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So I removed my radio, disconnected the alternator, and the courtesy light timer has been removed, and I still have a draw. I pulled the center gauges out and once disconnected the draw is gone. I have constant power to the orange wire (the clock) and the pink wire which if I am reading the wiring diagram right goes to the seat belt/ key warning buzzer and the gauges fuse. Is that circuit supposed to have constant power? I have 2 79s and my other one doesn’t have power to the gauges with the key off. I am also still trying to figure out why my brake light comes on when cranking over also. Any suggestions?
Jason
Jason
Gauge fuse should be off with key. Maybe key switch?
Drain? disconnect the negative post on battery. Place any 12 volt test light between the wire and battery post.
Pull ALL fuses. Light will be out (you hope).
Add fuses until light goes on. Pull that one out and add others until they are all in but the draw(s).
I take out drivers seat for this recreational activity. 4 nuts,done.
