Does the Curt Wiring Harness for a 2025 Jeep Grand Cherokee L Require Flashing from a Dealership?
Updated 03/22/2026 | Published 03/20/2026
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Question:
2025 Jeep Grand Cherokee L Limited Curt T-Connector Vehicle Wiring Harness with 4-Pole Flat Trailer Connector I have read places that when installing hitch wiring harnesses on Jeep Grand Cherokees you have to have the dealership flash it. Is that true or true with this harness?
asked by: Justin S
Expert Reply:
Hey Justin. The Curt T-Connector Vehicle Wiring Harness item # C27BR will not require you to go to the dealer and get your Jeep's computer system flashed.
The Curt item # C27BR is custom fit for the 2025 Jeep Grand Cherokee L. It's going to plug in directly behind your tail lights and send the signals through them to the 4-Way connector. It does not interact with your Jeep's computer systems.
I've linked the installation instructions below along with a video we made so you can see how the Curt item # C27BR installs.
What are you planning on using the wiring harness for? Are you towing a trailer or wanting to add lights to an accessory like a bike rack?
You can add this information, along with any other questions you have, where it says Add Comment.
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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
- Powered Converter
- No Tow Package
- 4 Flat
- Plug and Lead
- Plug-In
- Hidden
- CURT
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Tim R.
3/22/2026
I have a 22 Jeep Grand Cherokee Limited and bought it used without a hitch or harness. I put the hitch on for a bike rack, but added the harness while I already had the backend apart in case I want to tow a trailer in the future. I did not have to address any computer software and tested the harness with a plug in tester and all the lights lit up appropriately and have had no lights on the dash and it drives fine. There is a great video on Etrailer website I used to help with installation. I installed it last fall and have driven through harsh winter conditions and have had no issues. The harness works great, but not a lot of extra slack in the cord to get over to the hitch once module is mounted below passenger side rear tail light, but still is in a good position to attach a trailer plug