Wiring diagram for 2000 2500 with factory tow package

[DougKirby]

Hi, I have a factory installed tow package but the workshop manual I have doesn't cover this. The problem is that I don't have power at the Aux terminal of my seven pin outlet plug which is mounted in the truck tray, I use this to charge my fifth wheel batteries which power my trailer electric over hydraulic disc brakes. I have checked the relay and fuse in the fuse box under the hood on the drivers side and they are OK. Please email wiring diagram to -- email address removed --. Appreciate your assistance thanks.

 

[DavidC]

This is a 99, probably the same. Appears to be the 40 amp fuse or wiring/connector issue.

Dave

 

[PBJ2500CTD]

If you have power at the bumper connector and no power at the connector in the bed, follow/check for corrosion or breaks in the wiring from the bed connector to where they connect to the main/chassis harness. I believe there are splices for the bed connector going to the chassis harness. I don't see the AUX/5th wheel connector in the FSM for the 98 thru 02 years. The 02 schematic looks exactly like the 98 that Dave posted.
ALSO, Check your trailer clearance lights with the lights on. That would verify the 40A fuse is good.

 

[DavidC]

Dave

 

[DougKirby]

View attachment 102413

Dave

Hi Dave, thank you very much for your information and advice, Regards Doug.

 

[DougKirby]

If you have power at the bumper connector and no power at the connector in the bed, follow/check for corrosion or breaks in the wiring from the bed connector to where they connect to the main/chassis harness. I believe there are splices for the bed connector going to the chassis harness. I don't see the AUX/5th wheel connector in the FSM for the 98 thru 02 years. The 02 schematic looks exactly like the 98 that Dave posted.
ALSO, Check your trailer clearance lights with the lights on. That would verify the 40A fuse is good.

 

[DougKirby]

Hi Bruce, great thanks very much, what is the FSM please ? Clearance lights OK so looks like I have a broken or corroded wire or connection issue. Regards Doug.

 

[PBJ2500CTD]

FSM = Factory Service Manual. Looks like Dave has an electronic version. Makes for nice clean copies to post. I have the bulky book version. No fun to put on the scanner.
Check the connections in the 7 pin plug - the screws that connect the wires to the plug. Often times they get corroded over the years. Also, the evil scotch-locks or splices where the auxiliary harness meets the chassis harness. Hope that helps.

 

[DavidC]

I believe there are plugs on the Drivers side above the wheel well. They are between the wheel well and Drivers door and if I remember right are a real PIA to get to. I had to do it once to check wiring for the rear speed sensor and ABS.

Dave

 

[DavidC]

Hi Bruce, great thanks very much, what is the FSM please ? Clearance lights OK so looks like I have a broken or corroded wire or connection issue. Regards Doug.

Check that body plug at the hitch area carefully. I had an issue there once where it was giving me an ABS light above 45mph. I cleaned it up and applied dielectric grease to the cavity and have not had an issue since. Check the voltages at the 7 pin also as you may not have a truck issue but a trailer issue

Dave