Reverse light not lighting up (CJ7 1977)

[Rdavison39]

Okay - i guess i don't understand electricity. Trying to get the reverse lights working.

1. When i check voltage on the reverse light socket across the middle (+) and the metal socket that secures the bulb it reads 11.97 V (DC).
2. When i put the bulb in it does not light up
3. The parking lights, brake lights, and signal on the socket below work fine. When i check voltage on these lights is 12.35V (DC).
4. Hoping it was the bulb(s) i tested them out by connecting wire directly to the battery. All the bulbs worked fine.

So would it be that 11.97 V isn't enough power the bulb. Otherwise I just don't get why the bulb wouldn't light.

BTW - it happens in both RHS and LHS tail lights so i'm thinking i fundamentally am missing something.

 

[gert]

lol don't worry this circuit works backwards from normal circuits, it has power and is waiting on the neutral back up safety switch on the trans mission to make its ground circuit complete so the light can light up, sounds like your switch is bad or is unhooked from the trans

http://m.oreillyauto.com/h5/r/www.o....oap?model=CJ7&vi=1181124&year=1977&make=Jeep


Sent from my iPhone using Tapatalk

 

[HackFabrication]

What transmission do you have? T-150, T18, or TH400 (Quadratrac)?

 

[Rdavison39]

I'm not sure what transmission it is (how do i tell)

When i checked the reverse switch using a continuity tester, the circuit was complete when in reverse and no continuity when not in reverse. So I'm thinking its job is to complete the circuit when in reverse which it seems to be doing. I also took the reverse switch out from the tranny and inspected it and it looked and tested fine as well.

Not sure i understand the reverse polarity thing - will go look up on the web

 

[Rdavison39]

Also - i traced the wire back from the reverse switch mounted on the transmission. It surfaces in the hood with a 2 wires going into a connector that has 3 wires coming out of it. 2 wires go back to the fuse panel and w goes towards the engine but it doesn't connect anywhere. Its just hangin there. Should it connect to something or is it for another feature that this jeep doesn't have?

I did disconnect the wire coming from the reverse switch and tested the continuity - it has continuity when gear is in reverse....

Pictures attached..

 

[Rdavison39]

Okay - maybe i should try stuff out before posting. Sorry. I jumped the wires at the switch and the lights came on so must be a faulty switch.

Thanks anyway.
Ron

 

[gr8dain]

Okay - maybe i should try stuff out before posting. Sorry. I jumped the wires at the switch and the lights came on so must be a faulty switch.



Thanks anyway.

Ron

Try cleaning before replacing. I have cleaned mine multiple times.

 

[Lumpy Grits]

Ign switch has to be in 'run' to activate the circuit.
LG