Service VME - Location of Aux Brake Control Harness/Wire U86 Option

When servicing the vehicle with the VIN you entered, the following diagnosis might be helpful if the vehicle exhibits the described symptoms.

Location of aux brake harness wire when ordering U86 option:

The aux brake wire connector is on right side of vehicle under heater box, technician should see dark blue wire sticking out of harness about 76.2 mm (3 in).

The trailer harness connector in very rear of vehicle, the upfitter connector is behind cab on right side.

Please follow this diagnosis process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed. If these steps do not resolve the condition, please contact GM TAC for further diagnostic assistance. This diagnostic approach was developed for the vehicle with the VIN you entered and should not be automatically be used for other vehicles with similar symptoms.