I have a little problem that has had me frustrated for days! I have a 1929 chevy coupe with a 1978 camaro wire harness in it. I installed the harness about 3 years ago andeeverything worked fine. I took the whole car apart for paint and body work recently and ever since I put the car back together ive had lighting problems. The headlights, turnsignals, brake lights, and front marker lights all work but I have no dash lights or tail lights. Everything was working fine but a few days later a fuse blew so I replaced it and it blew about 6 more times. Now the fuse doesnt blow but I have no tail lights. I also replaced the relay and headlight switch. Any help is appreciated! I also purchased a 8 circuit painless wiring harness for another project and I was wondering if 8 circuits was enought to power everything on the car plus my electric water pump, fuel pump, and fan. Thanks
Fuses normally blow because the system protected by the fuse is short circuited. Meaning that what should be a hot wire is going to ground. On cars since who knows when the instrument light and tail lights are on the same fuse so the driver knows that he/she probably does not have working tail lights when the dash lights won't work. Your tail lights are going to be the 18 gauge brown wires. On that setup the stop lights run on the lt blue wires to the outboard lights and the left turn is yellow and right turn is dark green the turn lights being totally separate from the stop and tail lights. I'd start at one end and track the brown wires to make sure that you don't have a bare spot touching metal or otherwise grounded out. My guess is that somewhere between the switch and the lights the wire got pinched when something was clamped down on top of it or part of the wire got under something like a seat frame or a molding screw went through the wire. There probably isn't an old trailer plug hook up on it but from experience over the past 50 years old trailer wire hookups all too often contribute to tail or stop light problems.
I tracked the wires all the way to the rear and found nothing wrong. No cracked or pinched wires. The turn signal switch is out of the same camaro in a non tilt column.
The tail/dash lights don't go through the turn signal switch, so unless the turns/brake lights don't work forget about that. Sound like the problem is between the fuse panel and the light switch, so that's where I'd check. You may have killed the switch by trying multiple fuses, check to make sure you have continuity through that too. If the new switch isn't OEM, check it too; I've had poor luck with aftermarket switches...
Check the pins on the main connectors make sure none of them are bent and making contact with other wires in the connector. make sure wires are not pinched going through the fire wall or between something that was tighten down or a screw through a wire some where behind a piece of trim. I would also check all the grounds make sure all the grounds are clean and free of paint. a fault in a ground can cause lots of problems through a signal switch.I know some turn signal circuits are not are not part of the stop light circuit but some are. turn on the parking lights and check to see if you have any back feed through any other circuits. Do the same with the breaks and turn signal. just to be sure. check body grounds engine grounds. check to see if the connector on the turn signal switch has proper connection to switch and make sure it is in the correct way on some switches you can install the connector the wrong way. some where it has a short. I know you prob checked all this stuff but just trying to help . the only thing I can say is use a multi meter and check the continuity between the wires and trace the circuits until you find the problem. what I would do is first disconnect the light switch and pull the fuse check continuity between the connector where the switch is and parking light fuse and also to ground. then check continuity to all the parking lights and to the connector at switch. check the continuity between the connector and the cluster lights or if you have gauges or a tack check them too at the bulb Then conferm you have 12 volts power to the other side of the fuse pin the hot side. see if the voltage is about the same as there at the battery. if the voltage is way different then check the power lead from the source of power to the fuse there has to be a short there some where. if all that fails check the four way flasher when flashers go bad they can back feed to ground even when they are not on. I had this problem on my model a and the only way I found out was usualy when this happens the bad flasher causes the lights to either stay on or just not work but in my case it caused a back feed of ground and when I turned my signal on puked the fuse every time took replaced my flasher and back to normal and I cant explain why or how
Ok, so your prilimary search didnt find the problem. You say there's nothing to be found, yet the problem still exists. That means you need to get serious about looking this time the first attempts weren't deep enough to find it. De-bulb it and unplug the headlight switch then start checking the wires for continuity to ground. It's Methods not madness and mystics. It's obvious that something is different now vs when it was working. So what's happened in between is that you took it apart and put it back together. Go Over your work, the problem is there.
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