GMC TSB #PIE-0380B

2018 GMC Sierra 1500

You can still get the detailed info from GMC for this TSB. Call your local GMC dealer's service department & ask for a copy of TSB# PIE-0380B.

Summary: Engineering Information Â– BOTH Front Low Beam, High Beam, Day Time Running Lamps (DRL) and Turn Signals Inoperative Condition Some customers may comment that the front right hand AND left hand low beam, high beam, DRL, and turn signals are inoperative but the side markers still work as intended. If the turn signals are used, a turn signal bulb out message will be displayed. Cause GM Engineering is attempting to determine the root cause of the above condition. Engineering has a need to gather information on vehicles PRIOR to repair that may exhibit this condition. As a result, this information will be used to "root cause" the customer's concern and develop/validate a field fix. If you encounter a vehicle with the above concern, document the following information and contact one of the engineers listed below: Â• Is there any aftermarket electrical equipment installed on the vehicle? Â• Ask the customer about any aftermarket electrical devices that may have been recently connected to the vehicle. Â• Ask the customer about any high beam use or use of the headlamps in manual mode. Â• Ask the customer about the recent use of the remote start feature