2nd Gen Non-Engine/Transmission back-up lights

[BTighe]

my back-up lights arent working anymore. i checked all the fuse both in the cab and under the hood. i also checked the bulbs and there good too. what else do i need to check. i have a pair of 4" light bolted to the hitch and there not working either. im thinking theres a switch or sensor on the transmission that flipps on the lamps when i shft into rev. my manual doesnt show this so im kinda in the dark. any ideas would be apprieciated. thanks.

 

[Cowboy Medic]

First thing I would do is get a test light and put the truck in reverse with the key turned on so that you get what should normally be powering the lights active and then see if you are getting any power to the rear of the truck at the lights and at the point where you tapped in the new lights, If not then start tracing back. If you climb under the truck and watch where the wires come from the back of the truck you will be able to follow to where two of them jump up on the transmission, that is your switch. I don't remember for sure where it is and whether you need to get at it from the top or if you can get at it from the bottom.



If you are getting power to the back then the problem is your ground and you will need to either trace that and repair it or just make yourself a new one by tying it to the body somewhere.



Hope that makes sense and helps.



Jon

 

[Thomas]

The NV4500 switch is on the driver's side of the cover, forward of the shift tower. It's the only thing with wires going to it. It's replaceable from the bottom. You can rule out the rest of the backup lamp circuit by pulling the socket from the switch and jumping the two conductors in the socket (the rear lamps should light with the key in run position and the jumper installed).

 

[BTighe]

The NV4500 switch is on the driver's side of the cover, forward of the shift tower. It's the only thing with wires going to it. It's replaceable from the bottom. You can rule out the rest of the backup lamp circuit by pulling the socket from the switch and jumping the two conductors in the socket (the rear lamps should light with the key in run position and the jumper installed).

ok so i unplugged the wires to the switch there and checked the plug that is on the wring harness. it lit the test light so i assume that the switch is bad. am i right or is there something more. bulbs and wiring all look good. where can i get a new switch. thanks for the help

 

[Thomas]

... it lit the test light so i assume that the switch is bad. am i right...

By testing as you did, you only checked the circuit from the battery to the switch. Your test indicates that the problem is somewhere between where you stuck the testy light and the ground at the backup lights. It could be the switch, the wiring between the switch and the lamps, the sockets in the lamps, the bulbs, or the ground at the lamps.



It's likely the switch. To test everything other than the switch, stick a jumper (short length of wire) in the two holes in the socket removed from the switch (as I posted above) with the key in the rum position. The jumper will act like an always closed switch. If the lamps light with the jumper, your switch is bad.

 

[Thomas]

I just re-read your last post and my response. If you stuck the two probes of your test light into the two sockets on the plug and lit the test lamp then you were testing the entire circuit, minus the switch. If that's the case, the switch is toast.

 

[BTighe]

ill find a switch this week sometime. thanks for all your help. love this place Oo.