Mysterious Flashing h5 Error Code on P2 Trailer Brake Controller On a 2003 Ford E-250  

Question:

Expert Reply:

I can honestly say I have not heard of an h5 error message on the P2, # 90885. If the controller is upside down it could be SH which would indicate a short. If the trailer is connected and it shows this then that indicates a short on the trailer. You will need to make sure the trailer and vehicle side connectors are clean a free of corrosion on the pins and in the back where the wires attach.

Then you will need to make sure the wiring to the magnets is intact with no exposed strands touching the metal trailer frame. Make sure the magnet grounds are attached to clean and corrosion free bare metal surfaces. Visually inspect the magnets and if you can see the windings coming through then they will need to be replaced. To further test the magnets, you can follow the FAQ article I have linked.

If the error occurs when no trailer is connected, sever the blue wire a few inches back from the controller. Use a circuit tester such as # PTW2993 if you need one to test the end of the blue wire coming from the back of the brake controller. It should only show power when you apply the manual override. If it shows power at any other time, then the controller is bad and will need to be replaced.

If it checks out ok, then reattach the blue wire. Then you will make sure the vehicle side connector is clean and free of corrosion. It still shows up then there is a break or exposed wire somewhere between the controller and the connector at the back of the truck you will need to track down. I have linked an FAQ article on troubleshooting brake controllers for you.

expert reply by: Michael H

0