Electrical problems with my 77 280z

[kjphilippona]

This is not a daily driver and use it only when one of the other cars needs to be serviced, so it sit most of the time. I have a few things that have stopped working, the wipers, radio and fan motor. I have checked the vacuum lines and fuses and all are ok. i am not sure where to start looking for the problem

[beermanpete]

Start at the controls. The switches might be corroded from disuse. Sometimes exercising them will help. If that gets things going, even intermittently, it will give you a place to focus. If you need to proceed to electrical diagnostics, start by measuring for voltage at key places in the circuits of interest. Fuses, switches, device (motors,radio, etc.), and so on. If you get power all the way to the device then check its ground. Measuring for voltage on the ground side of the device. If voltage is present the ground is bad.

[kjphilippona]

Thanks

[EuroDat]

wal280z (wayne) has done a wondefull job making a coloured wiring diagram of the 77 280Z. See link for the last revision. It will come in handy when looking for places to check the voltage.

Chas

http://www.classiczcars.com/forums/electrical-s30/13131-color-wiring-diagram-280z-3.html#post430989

[Xenn]

Things to look for:

Wipers, if you have headlight problems as well, i would check the switch, if you get into it, pull the motor out and see if it still works, on mine the motor worked, but the scissor arms that connect to the wipers had rusted solid.

Radio, check fuses, also aftermarket or no? If it is aftermarket check to make sure your ground connection is good and it has a good connection to the ACC.

Fan motor, I upgraded to a honda civic motor and when I did I found out the previous owner had decided to do some rewiring under there, make sure all the connections are good between the heater controls and the fan motor, as well as anything that connects to the battery.

[SteveT]

Just solved a similar problem with my blue 77. The white/red tracer wire from the alternator to th forward fusible link had corroded in the harness. At that junction is two other wires, one of which powers the portion of the fuse block that supplies the functions that are in/op.

I had to strip back the black wrapping to expose the wires. I searched for the splice and found a crumbly spot. Cleaned it up and put in a butt splice ( didn't feel like doing a solder joint today). Still trying to find why I am not charging properly. Good luck! Steve T