Hopkins Impulse Brake Controller Showing E1/E2 Error Code
Updated 03/13/2019 | Published 03/12/2019 >
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Question:
Checked the brake controller after unhooked from the trailer, like you said it showed E1, but my controller is an impulse. Brake controller shows E2 sometimes
asked by: George S
Expert Reply:
The E1 error code on Hopkins brake controllers indicates that a trailer is not connected. If you do not have a trailer connected it will continue to display E1. If this happens when a trailer is connected then that could indicate a problem on the brake output circuit (Blue wire).
The E2 error on your Hopkins brake controller indicates a short to the blue wire. The most likely culprit is a dirty or corroded vehicle/trailer connector and is causing the controller to work intermittently. Clean both connectors and also check the back where the wires attach because corrosion can build up there as well.
Testing the brake controller is fairly easy. Sever the blue brake output wire near the brake controller leaving enough room to reconnect it and then apply the manual slide. Using a circuit tester like part # PTW2993, you should get output to the controller side of the wire you severed. If the manual slide activates the trailer brake output wire properly, try the brake pedal. If the brake pedal activates the brake output properly also then the problem is farther back either in the vehicle wiring or on the trailer.
If either the brake pedal or the manual slide are not functioning properly you will need to test the wires going into the brake controller. Make sure you have power entering the brake controller on the black wire. On the red wire you will only want power when the brake pedal is pressed.
If there is power on the red wire before the brake pedal is pressed you have connected the red wire from the brake controller to the wrong circuit. You would then need to find the brake switch wire that has power ONLY when the brake pedal is activated.
If these connections check out and the brake controller is properly grounded then there is possibly a problem inside the brake controller.
I am including a link to a video that will show you how to test the wiring on a brake controller.
The Hopkins controllers are somewhat prone to failing, when you replace it I would go with something a bit more reliable.
For a brake controller I would recommend the Prodigy P2 Brake Controller part # 90885. This is our best selling brake controller because of how well it works and how easy it is to setup. This is a proportional brake controller that senses the amount of braking the tow vehicle is applying and applies a proportionate amount to the trailer brakes.

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