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Service bulletins for the 2018 GMC Sierra

A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.

1723 on file from NHTSA, as of 2026-10-19.

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By component

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Only bulletins with component: Electrical system are shown. Show all

Bulletins, newest first
PIT5387J2021-02-16. Service bulletin. ELECTRICAL SYSTEM: INSTRUMENT CLUSTER/PANEL; BACK OVER PREVENTION:SOFTWARE; BACK OVER PREVENTION:DISPLAY FUNCTION. This Preliminary Information communication provides information to the technician how to repair vehicles that Instrument Panel Cluster, Radio, and Heater-Vent-Air Conditioning display blanks out, Bluetooth phone or Pandora connection dropped, the radio station or volume changes when operating the snow plow. Please advise the customer that engineering is aware of this concern and working on this issue.
16NA0192021-02-01. Service bulletin. POWER TRAIN; ELECTRICAL SYSTEM:SOFTWARE. This informational bulletin provides information on Transmission Adaptive Functions and Correcting Low Mileage Harsh Shifts, Slips, or Flares.
PIT5386F2021-01-25. Service bulletin. ELECTRICAL SYSTEM; BACK OVER PREVENTION. This Preliminary Information communication provides information to the technician about vehicles that are found to have a back-up alarm inoperative during the Pre-Delivery Inspection. On trucks equipped with the Back Up Alarm (RPO 8S3), the alarm will be intentionally left disconnected from the assembly plant. Technician will reroute the harness and plug it in.
20NA2122020-12-21. Service bulletin. POWER TRAIN:AUTOMATIC TRANSMISSION; SUSPENSION; ELECTRICAL SYSTEM; ENGINE. This technical bulletin provides repair information to correct a customer concern of IPC Gauges Inoperative or Fluctuate, No Crank, Start then Stall.
PIT5586F2020-12-14. Service bulletin. ELECTRICAL SYSTEM; ENGINE; EQUIPMENT; EQUIPMENT ADAPTIVE/MOBILITY. This Preliminary information communicates a customer concern of IPC gauges inoperative or fluctuate, No Start, No Crank, SIR Light / Service Airbag Message, Service Suspension Message, Radio display blank, Steering Wheel Controls (SWC) not illuminated, Turn Signal no audible feedback, HVAC controls inoperative. During diagnostics a technician may find any of the following DTC's: B1011, B1370, B3980, U0020, U0029, U007D, U0073, U0078, U0100, U0101, U0102, U0104, U0140, U0151, U0155, U0164, U0184, U0186, U0198, U0422. Dealer is instructed to check for logic lock of Serial Data Gateway Module or for Serial Data Gateway Module X1 and X2 connectors having terminal concerns and repair as needed.
1308116001F2020-12-07. Service bulletin. EQUIPMENT; ELECTRICAL SYSTEM; POWER TRAIN:AUTOMATIC TRANSMISSION. The intent of this technical bulletin is to identify aftermarket ALDL or DLC interface devices as potential sources for causing multiple customer concerns that do not have other diagnostic methods to identify them.
20NA2072020-11-30. Service bulletin. EXTERIOR LIGHTING; ELECTRICAL SYSTEM. This service bulletin informs the technician to inspect for a possible electrical concern at the ECM X2 electrical connector to correct a customer concern of Malfunction Indicator Lamp (MIL) Illuminated - DTC P0333 Set.
20NA2032020-11-30. Service bulletin. ELECTRICAL SYSTEM; EQUIPMENT. This informational bulletin explains how the regen works for the DEF system and how it works at different levels.
20NA0432020-11-30. Service bulletin. EQUIPMENT; ELECTRICAL SYSTEM. This informational bulletin advises the technician to not replace the TMAP sensor, clean it using air or harsh chemicals but allow time for the sensor to thaw.
PIT5387H2020-11-16. Service bulletin. EQUIPMENT; ELECTRICAL SYSTEM. This Preliminary Information communication provides information to the technician how to repair vehicles that Instrument Panel Cluster, Radio, and Heater-Vent-Air Conditioning display blanks out, Bluetooth phone or Pandora connection dropped, the radio station or volume changes when operating the snow plow. Please advise the customer that engineering is aware of this concern and working on this issue.
PIT5586E2020-11-16. Service bulletin. ELECTRICAL SYSTEM. This Preliminary information communicates a customer concern of IPC gauges inoperative or fluctuate, No Start, No Crank, SIR Light / Service Airbag Message, Service Suspension Message, Radio display blank, Steering Wheel Controls (SWC) not illuminated, Turn Signal no audible feedback, HVAC controls inoperative. During diagnostics a technician may find any of the following DTC's: B1011, B1370, B3980, U0020, U0029, U007D, U0073, U0078, U0100, U0101, U0102, U0104, U0140, U0151, U0155, U0164, U0184, U0186, U0198, U0422. Dealer is instructed to check for logic lock of Serial Data Gateway Module or for Serial Data Gateway Module X1 and X2 connectors having terminal concerns and repair as needed.
20NA1812020-10-26. Service bulletin. ELECTRICAL SYSTEM:SOFTWARE; ENGINE AND ENGINE COOLING. This technical bulletin provides a procedure to program the ECM if found the cause of the customers complaint.
20NA1762020-10-26. Service bulletin. ENGINE; ELECTRICAL SYSTEM. This technical bulletin provides a procedure to update the GPCM if found the cause of the customers concern.
20NA1572020-10-26. Service bulletin. EQUIPMENT; ELECTRICAL SYSTEM. This bulletin provides information on the Transport Mode On Message Being Displayed in the Driver Information Center (DIC) and/or Battery Light is Flashing and the procedures to turn the Transport Mode message ON and OFF.
20NA0552020-10-26. Service bulletin. ELECTRICAL SYSTEM. This technical bulletin provides a procedure to correct customer concerns of Instrument Panel Cluster (IPC) Gauges Inoperative, Numerous Driver information Center (DIC) Error Messages, No Brake or Electric Power Steering Assist, Transmission in Default Gear, No Reverse and/or Back Up Lights, No Daytime Running Lights (DRL), No Cruise or Adaptive Cruise and/or No Trailer Brake Lights.
18NA1612020-10-26. Service bulletin. ELECTRICAL SYSTEM. This technical bulletin provides a procedure for testing the battery cables for voltage drop, Checking for a bad ground at g218, Inspecting for a short at the starter B+ to shield and testing for a faulty battery.
20NA1572020-09-28. Service bulletin. ELECTRICAL SYSTEM. This bulletin provides information on the Transport Mode On Message Being Displayed in the Driver Information Center (DIC) and/or Battery Light is Flashing and the procedures to turn the Transport Mode message ON and OFF.
20NA0552020-09-28. Service bulletin. ELECTRICAL SYSTEM. This technical bulletin provides a procedure to correct customer concerns of Instrument Panel Cluster (IPC) Gauges Inoperative, Numerous Driver information Center (DIC) Error Messages, No Brake or Electric Power Steering Assist, Transmission in Default Gear, No Reverse and/or Back Up Lights, No Daytime Running Lights (DRL), No Cruise or Adaptive Cruise and/or No Trailer Brake Lights.
PIP5632C2020-09-14. Service bulletin. ELECTRICAL SYSTEM. This Preliminary Information communication provides information to the technician that General Motors Technical Assistance Center may ask for Global Diagnostic System 2 Session Log. Technician will need use Global Diagnostic System 2 to send the session logs to General Motors Technical Assistance Center for further assistance on the vehicle in question.
070842006O2020-09-08. Service bulletin. EQUIPMENT ADAPTIVE/MOBILITY; EQUIPMENT; ELECTRICAL SYSTEM. This informational bulletin provides technicians with information on available BCM calibrations to restore bulb outage detection on vehicles produced by a second stage manufacturer (Upfitter), and/or turn signals flash fast after factory box removed.
PIC5650H2020-08-10. Service bulletin. ELECTRICAL SYSTEM. This Preliminary Information communication provides information to the technician about vehicles that have an intermittent no crank, no start, or start stall concern with the security light coming on. Technician may find Diagnostic Trouble Codes B3055, B3060, and/or B3935. Technician should not replace any parts for this concern. If unable to duplicate the concern ask if the customer uses any Radio Frequency Identification Devices when the concern is present. Dealer should also direct their customers to the appropriate section in the Owner manuals that references that the device complies.
PIT5698A2020-08-10. Service bulletin. ELECTRICAL SYSTEM; EQUIPMENT. This Preliminary information communicates additional information on how a LIN bus operates and diagnostic tips when working on a LIN bus.
PIT5311F2020-08-10. Service bulletin. ELECTRICAL SYSTEM:WIRING; ELECTRICAL SYSTEM: INTEGRATED TRAILER BRAKE CONTROL. This Preliminary Information communication provides information to the technician on the steps to diagnose and repair vehicles that may have an intermittent "Check Trailer Wiring" or "Service Trailer Brake" message on the Driver Information Center. Technician will inspect and clean the ground wire (normally white wire) connection on the trailer side of the 7-pin connector. Inspect that the wires inside the trailer side connector are clean and securely fastened. If the vehicle?s 7-way connector socket terminals are deformed or have excessive wear, it will be necessary to replace the truck side connector with part number 23404450.
PIT5509G2020-08-10. Service bulletin. ELECTRICAL SYSTEM. This Preliminary Information communication provides information to the technician on how to diagnose and repair vehicle that may have a "Check Trailer Wiring" or "Service Trailer Brake System? message on the Driver Information Center when a trailer is connected to the vehicle. Diagnostic Trouble Code C1114 set in the Chassis Control Module. Chassis Control Module has to determine the type of trailer brake system that is being used. The Chassis Control Module can be sensitive to a variety of trailer wiring issues. The technician will need to make a trailer tester using Electric Trailer Brake Magnets and 7-way trailer connector to determine if it is a vehicle or trailer issue. If the concern is not duplicated with the tester installed, the vehicle is operating correctly and the focus should be on the trailer wiring or 7 way connector.
PIP57412020-08-10. Service bulletin. ELECTRICAL SYSTEM. This Preliminary information communicates to the dealer technician that if after replacing the valve body on an 8L45 or 8L90 transmission the vehicle will not move the valve body may be missing a plug and retainer bolt. Technician's are instructed to obtain and install a plug and retainer bolt kit from the GM Warranty Parts Center to address this concern.

The summaries are NHTSA's. Each bulletin's page links NHTSA's copy of the manufacturer's document.