Finding The Correct Brake Switch Wire For Adding Brake Controller on 1990 GMC 1500 Pickup
Updated 06/09/2023 | Published 06/08/2023
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Question:
I have a 90 GMC 1500 pick up truck. It has a grey wire on the top of brake switch and a green wire on the bottom side. How do I tell which wire to connect Red wire on controller too? Neither wire shows being hot even when pressing the brake pedal
asked by: James Q
Expert Reply:
The 1994 Chevrolet 1500 pickup is the closest vehicle we have installed a brake controller on in our shop to your 1990 GMC 1500. When we installed the Curt Triflex # C24VV with the Adapter # C51515 and Install Kit # ETBC7 as seen in the video linked below we found the yellow wire form the brake switch as the wire for connecting to the red wire on the brake controller. While I can't say for sure this is going to be the exact same on your GMC it should help you confirm the correct wire with a Test Light # PTW2993.
Product Page this Question was Asked From
Curt TriFlex NEXT Trailer Brake Controller - 1 to 4 Axles - Proportional
- Trailer Brake Controller
- Proportional Controller
- Electric
- Plug-In
- Under-Dash Box
- Under-Dash
- Up to 4 Axles
- LCD Display
- Single Trailer Only
- CURT
more information >
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