I've got an '87 Iroc L98/700R4. I can't figure out why my backup lights won't come on. The fuse is good. With ignition in run, shorting the dark blue (12v) and light green wires at the gear selector switch causes the lamps to come on, so that would mean the wiring portion is good, right? At this point I thought I'd just need to adjust the position of the gear selector switch. So with the ignition in run, I shifted to reverse and moved that thing as much in every position I could and got nothing. Is there any other explanation besides the switch itself? Is there a way for me to 'recondition' the contacts/switch? I haven't tried removing it and my neutral safety feature works.

 

Replace the switch.

The contacts wear out, and that’s what causes the problem.

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Happy Racing!

 

I have a similar problem with mine, My car is a 91 bird, 305 tpi with a 5 speed, I have replaced all the fuses, new bulbs, and a new reverse switch and I still have nothing, me and a few others cant seem to figure out as we all suck with wiring work, can anyone suggest anything?

 

I fixed my problem by 'refurbishing' the gear selector switch. If you take it apart you'll see that a couple springs are used to apply pressure to the contact that travels along in conjunction with the shifter. When I took mine apart, I re-lubed the internals and stretched the springs out a little so they applied more force, ...worked like a champ.

If you replaced the switch with one from a junkyard or similar it's within the realm of possibly that the 'new' switch has the same issue.

Also, make you you try jumping the appropriate wires to see if you can force the lights to come on. If you can't get the lamps on via that route, there's another gremlin to track down.