NHTSA Complaint #11519962 — 2021 GMC SIERRA 1500

ELECTRICAL SYSTEM issue reported to NHTSA

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Complaint Details

ODI Number	11519962
Vehicle	2021 GMC SIERRA 1500
Component	ELECTRICAL SYSTEM
Date of Incident	January 6, 2003
Date Filed	May 2, 2023
Mileage	N/A miles
Crash	No
Fire	No
Injuries	0
Deaths	0
Vehicle Towed	No
State	ME

Consumer Description

While towing a new 2023 Airstream trailer on Interstate route 95 in New Hampshire my GMC Sierra truck driver display flashes a " check Trailer wiring" error message. When this message appears all brake function to trailer is lost makeing driving unsafe. The connection sometimes can intermittently and continuously reconnect momentarily and brakes reengage for seconds until they disengage again with repeated "check Trailer wiring" error message . Sometimes the brakes just disengage end never reconnect until error codes is cleared by GMC dealership. It's extremely unsafe to pull off exit and have trailer brakes reengage because they jam with high gain because vehicle brakes need to be applied very hard to over compensate for "NO" trailer brakes. GMC dealership has identified certain error codes with their computer but NO suggested fix!

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