How to Find Brake Switch Wire on 2015 Subaru Forester for Brake Controller Install
Published 10/28/2016 >
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Question:
I HAVE PURCHASED THE PART 39523 BUT WHILE INSTALLING IT I FIND THE SUBARU BRAKE WIREING CONNECTOR HAS FOUR WIRES. WHICH WIRE DO I ATTACH TO THE COLD SIDEinch OF THE BREAK SWITCH AS REQUIRED BY THE WIREING DIAGRAM PROVIDED WITH THE ETBC7 4-WAY??
asked by: ANTHONY B
Expert Reply:
You are going to have to use a circuit tester like the part # PTW2993 to test the wires that feed into the brake switch to determine which is the correct wire to use. We haven't had the chance to install a controller on a Forester like yours so we don't have that info for you but testing the wires is pretty easy. We have heard that it's a red and white wire so start there.
Basically you just need to probe both wires while pressing and releasing the brakes. If the circuit has voltage with the brakes on but none when released that is the correct one to use.

Product Page this Question was Asked From
Tekonsha POD Trailer Brake Controller - 1 to 2 Axles - Time Delayed
- Trailer Brake Controller
- Time Delayed Controller
- Electric
- Plug-In
- Under-Dash Box
- Under-Dash
- Up to 2 Axles
- Indicator Lights
- Single Trailer Only
- Tekonsha
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