Reverse Switch Wiring

[phillay]

hi guys

 

my head is a bit messed  up so I am going to do a brain dump hoping someone could help.

 

I am chasing the last electrical problem that I have with my 240z, it's giving me the shivers, but I think I am really close so I am going to try and push on and not take it to the auto electrician (yet).

 

My reverse light doesn't work, I got a new reverse switch hoping it would fix it, no it didn't the strange thing is that I did a continuity test on the 2 wires on the existing switch (there are 2 switches, one has no wires on it, it's close to the prop shaft - i think this is a neutral switch, and one switch has 2 wire closer to the bellhousing - I am sure this is the reverse light switch). anyways back to the test, so I did a continuity test and my meter beeped. I am not sure why it's even beeping, as I followed the wire back into the cabin and one of the wire is cut off... must be shorting? I can not find the other snapped end, there are a few other loose wires which I don't know what they do, I've played around and no success so far.

 

I've managed to get everything else working on the z so far so I am quite familiar with how most things work and what colour wire does what.

 

here are a few things related to the reverse lights I know:

 

1) From the wiring diagrams I've looked at, the reverse lights draws it's power from the wiper fuse. my wipers work, so there is power at the fuse so the power source is there (assuming the reverse switch is correctly wired to this).

 

2) I've tested the earth from the bulb socket to the harness (it's shared with the tail lights) there is continuity there so that's all good.

 

3) all globes have been changed.

 

4) the power wire for the reverse light is red/blk and at the harness loom changes to red/blue - i think this is also a common wire colour used for power on my car's wire loom?

 

so what do you guys think I should do?

 

1) just run a new wire from the reverse lights to the switch and then from the switch to the wiper fuse? (is it as simple as it sounds?)

 

2) pull out the dash, unplug the 3 big loom harness plugs look for the reverse light wires and go from there? (there is probably just a simple break somewhere under the steering column?)

 

 

sorry for the big and messy post, any help is appreciated.

 

 

regards,

 

Phil

 

 

 

 

 

 

 

 

 

 

 

[Zedman240®]

Have you tried just touching the two wires that plug into the switch together? (not the switch side, loom side) and see if the reverse lights come on. If they do, switch is the problem. To test the switch, put your multi meter on continuity, and put each probe in each switch plug and put the gearbox into reverse and you should hear the multimeter beep. If not, swotch or wiring is toast. If you don't get the lights to come on by shorting out the two wires on the loom, check fuse again and bulb holder, wiring etc..

[phillay]

Hi dimi yes I have tried shorting the wire loom side, no lights but for some reason theres continuity thats why I think it has short itself somewhere. The circuit seems simple enough but for some reason im unable to easily traceable. If the wiring is broken I guess I will need to run a new wire by intercepting the red/black wires at each tail light plug anf go from there?