Back up lights.

Help!

I have a '71 CJ 5 and the backup lights don't work. Bulbs look ok and I installed a new switch in the tranny and still no luck. Then I look behind the dash and see a couple of loose wires hanging next to the ignition switch, one's green with a white stripe and the other looks to be solid green (Chiltons says the back up light wires are green/white and tr. whatever tr. is). Also, there are two unused conductor posts on the back of the ignition switch, at about 10 and 11 o'clock, I think.

Please advise.

 

tr. means trace, ie a stripe.

I would not trust the Chilton's wiring diagram much.

Do you have a volt/ohm meter? I would start with the switch on top of the transmission, and see if it works and if you have power there. The switch works by connecting the +12V supply to the backup lights when the transmission is in reverse. We went through this before. Have you checked the switch?

With the key on, if there's no power to that switch, then you might have a blown fuse, or a disconnected wire under the dash,. If there's power to the switch, and the switch actually works (ie closes when the tranmission is shifted into reverse) then you probably have a break in the wires to the backup lights.

 

Thanks, would have never guessed that's what tr stood for.

I did like you told me and checked with a light and a meter. No power at the switch. That's what led me to look for a loose wire. Do the lights get power from the back of the iginition switch? If so, do they attach to the unused posts that I saw?

 

Some ign switches have a term that is for accessories that is hot with key in acc position and in the on pos also. If you have this term (test with test light) I would use it. Handy when doing stuff behind jeep when not running. Otherwise you connect to a term that goes batt hot with key on. Warning Warning--PO may have disconnected wires due bad short so be sure you are fused in that green wire with white tracer.

 

Is there a way to check for a short?

 

Measure the resistance to ground for the wire you plan to connect to the ignition switch. I'd suggest you trace it through to the backup light switch on the transmission, if you can. Another simple test would be for continuity between the connector at the ignition switch and the connector at the transmission.