back up lights?????HOT wires

[Elkaholic11]

I'm now down to only my back up lights no working. I put a sm465 tranny with the back up switch on the drivers side of transmission. I also put a new painless harness in the pickup. The harness has two wires that say back up lights. One wire goes all the way back to the light and the other originates from the fuse. The switch has two prongs and when I attach both wires the lights don't come on but the wires get HOT, no blown fuses either. Could this be a ground issue? The wires only get hot when in reverse and only in the cab not back by the lights. I cleaned the light housing metal before I installed them. I know the switch is working because the wires only get hot when I put it in reverse, what would make the wires hot but not get power back to the lights?

[panhandler62]

If the wires get hot they are conducting current (and a fair amount of it at that.)

If the wires get hot but the lights don't come on then the current is finding its way back to the chassis ground somewhere besides going through the bulbs.

I would start by disconnecting the lead going to the lights from the switch. Does the wire coming from the source (the fuse) still get hot? If so; the switch is bad -- it is shorting to ground somehow. If not, then the problem lies in the lead back to the lights. Reconnect the lead to the switch and disconnect it at the other end and see if it still gets hot. If so.... it is pinched somewhere. If not ... measure from the loose end to chassis ground. If you have a voltage drop (or current if you would rather measure that) then the problem is at the light housing.

[fixit-p]

Originally Posted by Elkaholic11

I'm now down to only my back up lights no working. I put a sm465 tranny with the back up switch on the drivers side of transmission. I also put a new painless harness in the pickup. The harness has two wires that say back up lights. One wire goes all the way back to the light and the other originates from the fuse. The switch has two prongs and when I attach both wires the lights don't come on but the wires get HOT, no blown fuses either. Could this be a ground issue? The wires only get hot when in reverse and only in the cab not back by the lights. I cleaned the light housing metal before I installed them. I know the switch is working because the wires only get hot when I put it in reverse, what would make the wires hot but not get power back to the lights?

It would be helpful if you would post the part number or schematic of the kit you are working with.

Above you stated "The wires only get hot when in reverse and only in the cab" do both wire run back into the cab?

Two things could cause the wires to get hot as you describe 1 is low resistance to ground (short circuit) in which case the fuse should blow.

The other is excessive resistance which limits current flow but creates a voltage drop (heat) but that would require a completed circuit and wouldn't normally be in a section of wire unless there was a resistor or resistance present.

[fixit-p]

I see you posted the part number in the other thread I'll take a peep at the schematic.

[Elkaholic11]

So I found the problem with the lights and hot wires. The wire going into the back of the housing has a spring that was making contact with the housing. Every way I tried to fix the spring issue I couldn't get it to work so I went and bought 2 light sockets and pigtail with a hot and ground wire similar to the socket for the side marker lights and integrated them into the back up light housing. This made a more reliable ground and the lights work great now!! Thanks for all of your advice and help.