I posted elsewhere , but i need an answer to this asap.

https://www.dieseltruckresource.com/...threadid=76378

thanks.

 

The easy place to start are fuses and flashers in the inside fuse box.

From what little I have seen on the wiring, I would check the turn signal/ 4 way flasher switch. I think the break light switch on the break pedal is even wired though it. If this switch is bad it could keep the lights from working. From the switch to the light sockets should only be wires and plugs in the wiring harness.

If this is all good I would find the wires under the dash where they plug in. Then check each wire to the turn signal switch and 4 way flasher switch. Also check the break light switch and wiring. The next thing would be to check the each bulb. A ohm meter and a long wire to make it reach the light bulb sockets should be all thats needed.

Hope this Helps,
Rodney

 

Sounds to me like your multi-function switch has given up the ghost. There have been other posts of a similar nature and it was the multi-function switch. Try doing a search for 'turn signal switch' and you will see what I mean. Far as the timing, probably just coincidence.
Tom

 

I thought the mautifunction switch was probably the culprit myself , since the dash was apart a while back for the high beam indicator, and it pointed mostly at the switch.

The part that made me wonder was the brake lights , but if they are wired through there somehow , that explains it.


I guess i will ask for a PO tomorrow to go get a new switch and hope that solves it.


I think the timing was coincidence also , being that the charge wire was hooked to nothing , the last ape who wired the trailer lights tied it up out of the way. It was just looking like my fault because i had just been working around the trailer plug, so it made me look really bad.

I hope this solves it.

thanks guys. Jayme.

 

The brake lights do go throught the multi-function switch since each brake light is cancelled when that particular turn signal is on. I have not tried to change one myself, but have read that it is not real difficult.
Tom

 

well , the switch is not the problem , there is problems elsewhere.

Does anyone have a wiring diagram for the lighting circuit on these trucks? as well as the trailer wiring circuit.

I need to know where that red wire with the white stripe goes on the truck.

 

Jayme, If you get the chance go get a Haynes manual #30041 and it should have the schematic(s) that you want. If you tell me what wire you are talking about I can try to find it for you.
Tom

 

on the rear trailer harness it is a red wire with a white stripe , it has constant 12v , and 14 when the truck is running/charging.

 

I think that wire goes right up to the underhood fusebox- 40 amp cartridge fuse.
Also check the bulkhead connector under the dash on the left. There are several connectors around it and we usually disconnect them when we remove the dash.