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Electrical Tips

Note: ALWAYS disconnect the battery before working on the electrical system!!

1. My backup lights and/or neutral safety switch doesn't work. First, check the obvious, such as bad bulbs (yes, they can both burn out at the exact same time), the fuse, and dirty sockets. If this is not the cause of your problems, check the switch. The switch for the backup lights is located on the right hand side of the steering column about half way down and has four wires coming from it. The brown wires (they look like lamp cord) are for the backup lights. Set the parking brake, turn the key to the run position (but don't start it!), put the car into reverse and check the continuity. If the switch is bad, remove it from the car and take the cover off. The cover is held on by four small metal tabs. Make sure that you have the cover facing up when you remove it or you may loose parts from the contacts. Remove the white plastic holder, two springs, and the sliding contact. Inspect the contacts for damage and clean them if they're in good shape (use contact cleaner or 400 or 500 grit sand paper). Wipe any debris out of the housing, reassemble the contacts into the housing and place them in the plastic part of the switch. Lightly lubricate the back of the metal top where the contact holder rubs with white grease and put the top back on the switch. Bend the metal tabs back and put it back in the car. This will also fix a troubled neutral safety switch.
2. I'm in the middle of rewiring the car and I can't figure the headlight switch out. Hook both Red wires to +12v constant power (make sure it's fused!), Brown goes to the headlight dimmer switch, Orange goes to the dash lights, White goes to the lights that come on when the doors open. Light Blue goes to the parking lights. Black goes to door jamb switches and courtesy light grounds
3. My wiring is hosed. What wiring harness did you use? I used a 12 circuit universal harness from Painless Wiring. You can get this from any performance shop for about $250. The instructions are top notch and the kit has everything you need except for connectors for the high beam lights (it's setup for a two light car). If you are doing a restoration (instead of making a street machine like I'm doing), this harness uses GM color coding and does not look anything like the factory wiring. The wiring you get is at least one wire size higher than what the car came with and feeding the wires through the factory grommet was a challenge. The only other tough part I ran into was the headlight switch wiring (see above).
4. I'd like to add hazard lights to my car. How do I hook them up? To hook up hazard lights, you will need the following:
   • 4PDT 12 volt relay rated at 5 amps
   • Base for relay
   • SPST Automotive switch rated at 20 amps
   • Flasher (try Wagner 552 or equivalent)
   • 20 amp fuse and holder
   • 12 and 14 AWG wire
   • Terminals for flasher, switch, and ground wire
   • Soldering iron, solder, electrical tape, heat shrink tubing
   • Heavy Velcro or a bracket to mount relay
   • Click here for wiring diagram.(5K GIF)

   Determine where you are going to mount the relay and switch. Run 12 AWG wire from a constant +12 volt source with nothing else on it to the fuse (If you run a wire directly from the battery, make sure to put a fusible link between the battery and your new wire). Run 12 AWG wire from the fuse to the switch. Run 12 AWG wire from the switch to the coil input on the relay base. Run 12 AWG wire from the relay base coil output to ground.

   Solder a length of 14 AWG wire across the input side of the relay base. Solder a a length of 12 AWG wire to the 14 AWG wire. Connect this wire to the flasher. Run a second length of 12 AWG wire from the fuse to the flasher.

   Clip the terminals off of the normally closed contacts (on the base). Run a wire from each of the normally open terminals (on the base) to the wires for the turn signal lights.

   Note: Make sure that all connections into the factory wiring are soldered and covered with heat shrink. It only takes a little extra time to do this and you will end up with a connection that will not corrode.

5. Okay, I've got the backup light/neutral safety switch rebuilt. How do I adjust it? Put a small wire (such as a paper clip) into the hole in the switch body and set the parking brake on the car. Reconnect the wires to the switch and put the car in neutral. There is a pocket in the slider for the shift linkage in the steering column. Put the nub on the switch into this pocket and install the screws. Remove the wire from the hole in the switch body and you should be able to start the car in either Park or Neutral ONLY. If it starts in any other gear, make sure that the nub on the switch is in the pocket in the steering column and that the screws are tight.

Last Updated 01/05/04 09:00:04 PM