My 2000 dodge ram 2500 4x4 back up lights quit working. I replaced the back up light/neutral safety switch, the light bulbs, and the sockets, but the back up lights still won't come on. Any ideas?

 

How are they fused? Check that first. Then follow the power. start at he back and work your way foward to see where you lose power. I believe it is the Black and purple wire on your truck.

 

Sorry. Forgot to mention that I also changed the fuse, located in socket 7 on the drivers side of the dash board. This didn't fix it, either.

 

Grounded well?

Even though the switch is new, doesn't mean it is good. Maybe try jumping the plug at the switch.

Is it possible that there is an issue inside the transmission and so the switch isn't being depressed?

 

When you say neutral safety switch, did you mean the reverse light switch in the top of the tranny? When you changed the fuse, did it pop the fuse again?

 

Is this truck an automatic? As suggested above, the place I'd start is jumping the wires together at the switch connector. Regardless of what trans you have, that'll rule out the possibility of an internal transmission problem.

Having a wiring diagram would help, but generally I would then work my diagnosis both ways, starting from the switch. Does the switch have power that should be coming to it from the front? Is there continuity to the rear of the truck from the switch, through the bulbs to ground?

Do a quick visual on the rear light harness down the frame to the lamps. Has someone done a sloppy job splicing in trailer wiring and the splices are now corroded through?

Good luck. Hope this helps.

 

tried jumping the switch contacts, no back up lights. there is voltage to the switch. when the switch is unplugged, the truck won't start unless the switch is jumped. transmission is an automatic. the switch is located between the fluid lines on the driver's side of the transmission. don't know anything about a switch on top.

 

Have you checked your bulbs?

 

Sorry,I see you did.

 

If I remember correctly, you jump the 2 outer terminals together (with key on) to operate the reverse lamps. The center terminal gets grounded by the switch in park and neutral to allow the starter to operate.

So, if one outer terminal does indeed have power with the key on, the fault must be downstream of the switch. I believe the wiring goes directly from the switch to the reverse lights, although you should consult a diagram before you take my word for it; I haven't looked at that circuit for a number of years.

At the rear of the truck, you will find a connector or two, where the wiring harness splits off to the two lamps. With the key on, truck in reverse (emer. brake firmly set and wheels chocked for safety) you can check those connectors for power. I can't remember which wire- I think it's purple, or has a purple stripe.

 

I know my backup lights dont come on unless i hold the shifter halfway between park and reverse, havnt tried to adjust it yet too many other things to do first, might not hurt to try and slowly pull the shifter down and get someone to see if they come on at one point.