Activator IV Not Working Correctly on a 2008 GMC Sierra Pickup

Question:

I wired the activator IV to my 2008 GMC Sierra as per the instructions. I have triple checked the wire diagrams, connections and fuses. According to the instructions, with no trailer plugged in I should see a decimal point when I depress the brake pedal and I do not. I do see it when sliding the manual switch.

asked by: Peter

Expert Reply:

According to the manufacturer, when there is no decimal point on the Activator IV, # 5504, when the brake pedal is pressed, there are two possibilities.

First, use a circuit tester, item # PTW2993, and verify that the red wire going into the controller has power only when the brake pedal is pressed.

Next, the fuse in the stoplight circuit should be checked.

The only other possibility is that there is a bad circuit inside the brake controller, and it will need to be replaced. Brake controllers have no user serviceable internal parts.

If you determine that a new brake controller is needed, I recommend a proportional brake controller, like the prodigy P2. This controller will provide smoother braking and help with wear on both the vehicle and trailer brakes.

expert reply by: Robert G