Troubleshooting 4-Way Wiring Relays Wont Install on 2018 GMC Terrain
Updated 11/22/2022 | Published 11/19/2022
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Question:
I have a 2018 terrain. I installed the wiring harness per video but the relays dont snap into the block. What else do I need?
asked by: Roy
Expert Reply:
It sounds like you're installing the Curt # C56375 on your 2018 GMC Terrain. This is designed for the factory tow package. Since your relays don't snap into the K1 and K3 positions it sounds like the terminals are missing from the relay cavity. This means you need the T-One Vehicle Wiring Harness # 118764 instead. This wiring harness is designed for the Terrain without the factory tow package, and no relays are required.
Product Page this Question was Asked From
Curt T-Connector Vehicle Wiring Harness with 4-Pole Flat Trailer Connector
- Custom Fit Vehicle Wiring
- Trailer Hitch Wiring
- Vehicle End Connector
- No Converter
- No Tow Package
- 4 Flat
- Plug and Lead
- Plug-In
- CURT
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