NHTSA Complaint #11591633 — 2024 GMC SIERRA 2500

Brake control module disconnects trailer brakes while towing. Apparently a known issue with trailers equipped with solar battery chargers which have higher charge than vehicle battery. It feeds back into the trailer brake power module causing it to shut down. The vehicle has an integrated trailer brake controller as it is specifically designed with primary function as a tow vehicle. Shutting down the integrated trailer brake controller results in loss of trailer brakes. Not having trailer brakes is critically dangerous. GM has issued a TSB #23-NA-149 specifically addressing this known defect. Unfortunately, GM refuses to authorize its service technicians to replace the defective brake controller unless they experience the defect personally - the policy is to disbelieve the customer with the defective vehicle. Effectively, this requires providing the trailer to the service tech to drive around until the brakes fail, thus creating another dangerous situation for a tech who may or may not have experience driving vehicles over 50’ in length. Thus, it would appear the best remedy is to enforce a recall to replace the defective brake controller before someone is harm by loss of brakes, since GM requires its techs to encounter a loss of brakes before authorization of replacement of the known defective unit. This happened over 25 times during a trip last week. This fact situation reveals why your Administration actually exists - to protect the public from harm.