1970 with wiring nightmare
Thread Starter
Instructor
Joined: Nov 2018
Posts: 193
Likes: 70
From: Chicago
1970 with wiring nightmare
Working through a bubba inspired electrical nightmare. Car is a 1970, 454, 4-speed car. The person added a second 2-pole connector to the rear of the car and did not use a back-up light connector. Thus, when you hit the turn signal, both of the right or both of the left lights blink.
- Turn on the headlights and all the rear light and marker light work... yeah
- Turn the left signal on and the dash light flashes on the left and the left front and rear blinkers work... yeah
- Turn the right turn signal on, and the dash LEFT light blinks, rear blink on the right as they should and BOTH front signals flash... pretty amazing to see
- No flashers (could be the flasher fuse on the block)
- No brake lights (could be the brake light with)
Melting Slicks
Joined: Feb 2018
Posts: 2,327
Likes: 721
From: Marietta GA
You should also look at the grounds for the taillights, when they are bad, apply, types of strange things will occur. Look at a wiring schematic to see if someone has monkeyed with the wiring.
Race Director
Joined: May 2006
Posts: 10,936
Likes: 478
From: EAST TENNESSEE
bad grounds can cause all sorts of weird problems especially with Corvettes! Check your grounds first. I’d check my turn signal and brake switch out with an ohm meter.
Safety Car
Joined: Nov 2002
Posts: 4,182
Likes: 1,178
From: out of nowhere
All sound advice above. The grounds on each side (driver’s/passenger’s) have a jumper between the metal housings, then a ground wire is ran over to the frame. Any of those could be lacking, as in corroded, rusted, disconnected. On top of that, the jumpers and ground to frame rely on/are bolted to the metal tail light housing studs. Those studs are often very corroded. All 8 of mine were so corroded, rusty and weakened that they snapped upon trying to remove them, even after wire brushing the threads and multiple soakings with PB Blaster.
To get at everything adequately though a drop of the tank and exhaust may be in order. This area is the first area I’m tackling on my ‘71 and has taken considerable hours to get to the point where I’m close to getting them back in there. I did buy a new rear harness though. I figured if everything else was that bad, why risk putting everything back up in there only to have to pull it again due to a wiring issue. Best of luck to you!
To get at everything adequately though a drop of the tank and exhaust may be in order. This area is the first area I’m tackling on my ‘71 and has taken considerable hours to get to the point where I’m close to getting them back in there. I did buy a new rear harness though. I figured if everything else was that bad, why risk putting everything back up in there only to have to pull it again due to a wiring issue. Best of luck to you!
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Thread Starter
Instructor
Joined: Nov 2018
Posts: 193
Likes: 70
From: Chicago
Cleaned the grounds and replaced the turn signal switch. Now the turn signals work as planned. I did not get a chance to replace the brake light switch, but will work on the brake lights next week. There was one black wire cut on the harness, so this surely was part of the problem.
Safety Car
Joined: Nov 2002
Posts: 4,182
Likes: 1,178
From: out of nowhere
Cleaned the grounds and replaced the turn signal switch. Now the turn signals work as planned. I did not get a chance to replace the brake light switch, but will work on the brake lights next week. There was one black wire cut on the harness, so this surely was part of the problem.