Brake Controller Recommendation and Install on a 2008 Freightliner Sprinter

Question:

Is there a custom wiring adapter for connecting trailer brake controller Tekonsha or other to 2008 Freightliner Sprinter underseat green plug?

asked by: Bruce L

Expert Reply:

We don't have a custom harness available for installing a Tekonsha P3 part # 90195 to the connector on your 2008 Freighliner. That would be something you would need to get from Freightliner, or you could just remove the green plug and hardwire the controller to it assuming it is the brake controller install port.

You would need to use a circuit tester like part # PTW2993 to determine the functions of the wires and then connect the controller to them as needed. The red wire of controller would need to go to the wire that sees voltage when the brakes are applied and none when released. The black wire to the wire with voltage all the time.

Ground the tester to the constant 12-volt power wire, then probe the remaining two wires. The wire that lights the tester will be the ground, the other will be the brake output circuit.

expert reply by: Jameson C