hi guys, I am in the process of installing a trailer brake controler in my '98 1 ton dually 12 valve truck. My problem is I have found the factory plug in connector under the dash but as this truck did not have the factory tow package the blue wire that would normally go to the 7 pin connector at the rear of the truck doesnt seem to be any where at the rear of the truck, does any one know where the wire terminates after it leaves the plug in connector under the dash. Thanks for any help in this matter

 

If the 7 pin plug is on the truck the blue wire should be hooked up. If not look under left hand side in the wiring bundles in the back should be there.

 

On my buddies '96, the blue brake wire exited the underdash area through the firewall and was routed with the harness down the frame rail. There was an inline connector in the wiring harness about even with the firewall. The blue wire went into one side of the connector and just terminated there..... no blue wire coming out of the other half of the connector.

 

Mechanos,
Thanks for the info! It was exactly where you said it would be and the install went well. Soldering was a pain due to the limited space but the wire is now installed and I now have trailer brakes!
Two beers and a few tie wraps later and my truck is complete.