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

Bulletins, newest first
PIP57402020-08-10. Service bulletin. ELECTRICAL SYSTEM. This Preliminary information communicates to the dealer an issue where a customer may have incorrectly received a notification advising of a starting syetem issue with their veihcle. Dealer advised to inspect for a legitimate issue, if one found, diagnose accordingly.
PIT5206G2020-08-10. Service bulletin. EQUIPMENT ADAPTIVE/MOBILITY; ELECTRICAL SYSTEM; POWER TRAIN:AUTOMATIC TRANSMISSION; SERVICE BRAKES; EQUIPMENT. This Preliminary Information communication provides information to the technician with the steps on diagnosing and repairing vehicles that may have unwanted grade braking, reduced engine power with no Driver Information Center messages ? Brake Pedal Override Feature ?, transmission busy or frequent shifting up or down, and Diagnostic Trouble Codes P057B, P057C, and/or P057D may or may not be set. Technician will use this preliminary information to find the brake pedal position data parameters in the scan tool, and also to provide some additional diagnostic help. These issues may be caused by an incorrect brake pedal position sensor input to the engine control module. Technician will verify with the scan tool if the engine control module has the correct parameters for the brake pedal position sensor. If an engine control module brake pedal position sensor relearn is performed, the truck may be temporarily repaired until the intermittent wiring issue between the engine control module and brake pedal position sensor occurs again. On 2014 and newer trucks inspect and repair any damage to X115 and X119. On the 2014 and previous trucks inspect and repair any damage to X205.
PIT57452020-08-10. Service bulletin. ELECTRICAL SYSTEM; SEATS. This Preliminary information communicates and issue with the memory seat module waking up the low speed GM lan bus and causing a battery draw.
20NA1392020-08-10. Service bulletin. ELECTRICAL SYSTEM. This technical bulletin provides a procedure to check and tighten the B+ at the starter for proper torque.
20NA1322020-08-10. Service bulletin. ELECTRICAL SYSTEM. This warranty administration bulletin provides policy information on the requirements for battery testing and warranty replacements.
070849020Q2020-06-22. Service bulletin. ELECTRICAL SYSTEM. This informational bulletin provides information for the IPC odometer programming method quick reference guide.
060089029T2020-06-22. Service bulletin. ELECTRICAL SYSTEM: INSTRUMENT CLUSTER/PANEL; EQUIPMENT. This informational bulletin includes information on Interior Cleaning - Instrument Panel (IP), Hard or Plastic Surfaces, Seats, Carpet, Leather, Vinyl, Fabric Cleaner, Stain Remover, Restorer - Product Availability.
060089029S2020-06-22. Service bulletin. ELECTRICAL SYSTEM: INSTRUMENT CLUSTER/PANEL; EQUIPMENT. This informational bulletin includes information on Interior Cleaning - Instrument Panel (IP), Hard or Plastic Surfaces, Seats, Carpet, Leather, Vinyl, Fabric Cleaner, Stain Remover, Restorer - Product Availability.
20NA1132020-06-22. Service bulletin. STEERING; ELECTRICAL SYSTEM. This technical bulletin provides repair information to correct a customer concern of Action Required Steering Assist is Reduced Drive with Care Or Service Power Steering Message And Or Current Power Steering Control Module DTCs.
20NA0552020-06-22. Service bulletin. ENGINE; ELECTRICAL SYSTEM. This technical bulletin provides a procedure to program the ECM to correct the customers concern.
20NA0552020-06-22. Service bulletin. ENGINE; ELECTRICAL SYSTEM. This technical bulletin provides a procedure to program the ECM to correct the customers concern.
PIT5593B2020-06-15. Service bulletin. ELECTRICAL SYSTEM; POWER TRAIN; STEERING. This Preliminary information communicates a power steering control module calibration error that does not allow its DTC's to transition to history and they always stay current, which can mislead a technician diagnosis. Dealers are to reprogram the power steering control module with updated calibration which will allow DTC's to transition to history if the issue that caused the DTC(s) are now longer present.
PIP5429A2020-06-15. Service bulletin. ELECTRICAL SYSTEM; POWER TRAIN. This Preliminary Information communication advises the technician that the customer may experience a 2-3 slip or flare after the vehicle has been sitting for a period of time. Technician can update the Transmission Control Module if working on a model year 2007. On all other model years dealer should communicate to the customer this condition is a normal operating characteristic of their vehicle.
PIP5700C2020-06-15. Service bulletin. ELECTRICAL SYSTEM. This Preliminary information communicates to the dealer technician that the part numbers for the internal wiring harnesses for the 8 speed RWD transmissions are not listed in the Electronic Parts Catalog. Technicians are to refer to the information provided in this document to obtain the internal wiring harness part numbers by application.
18NA1802020-05-26. Service bulletin. EQUIPMENT; ELECTRICAL SYSTEM. This Warranty Administration Bulletin Provides High Voltage Battery Exchange Process Information.
PIT5195F2020-05-11. Service bulletin. ELECTRICAL SYSTEM. This Preliminary Information communication provides information to the technician about vehicles that the speedometer needle appears to be inaccurate. Dealer should advise the customer the specification for speedometer needle accuracy is +/- 2 MPH at any given speed when looking straight at the needle.
N192265660-012020-04-20. Service bulletin. ELECTRICAL SYSTEM; VISIBILITY:DEFROSTER/DEFOGGER/HVAC SYSTEM:REAR WINDOW. Customer Satisfaction Program - Certain 2014-2019 model year Chevrolet Silverado and GMC Sierra vehicles equipped with a power sliding rear window (RPO A48) may have areas of high electrical resistance on the rear defroster circuit. This could be caused, in part, by mechanical stress from opening and closing the rear power window, intrusion of debris, and use of the rear defroster. Over time, this condition could generate heat that could melt the areas surrounding the circuit. In rare instances, this heat could cause a non-propagating fire, increasing the risk of property damage or injury. Dealers will replace the buss bar covers and contact cover. If the rear window or sliding glass assembly appears damaged due to an occurrence of high electrical resistance on the rear defroster circuit, they should also be replaced.
N192273630-022020-04-20. Service bulletin. ELECTRICAL SYSTEM; EQUIPMENT ADAPTIVE/MOBILITY. Emission - General Motors has decided to conduct a voluntary emissions recall involving certain 2016-2019 model year diesel engine vehicles. The engine control module (ECM) in these vehicles may not adequately diagnose or illuminate the malfunction indicator lamp (Check Engine Light) when frequent regeneration of the diesel particulate filter (DPF) occurs. Dealers are to program the engine control module (ECM) with corrected software.
N192273631-012020-04-20. Service bulletin. FUEL SYSTEM, GASOLINE; ELECTRICAL SYSTEM. Emission - General Motors has decided to conduct a voluntary emissions recall involving certain 2017-2018 model year diesel engine vehicles. The engine control module (ECM) in these vehicles may not adequately diagnose or illuminate the malfunction indicator lamp (Check Engine Light) when frequent regeneration of the diesel particulate filter (DPF) occurs. Dealers are to program the engine control module (ECM) with corrected software.
PIT5509F2020-04-13. Service bulletin. ELECTRICAL SYSTEM; SERVICE BRAKES, ELECTRIC. 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.
PIT5490B2020-04-13. Service bulletin. ELECTRICAL SYSTEM; SERVICE BRAKES, ELECTRIC. This Preliminary Information communication provides information to the technician about vehicles that may have a Service Trailer Brake message in the Driver Information Center. Also the vehicle will have a Diagnostic Trouble Code U0415 set. Technician will fill the master cylinder brake fluid reservoir to the maximum level.
PIT5586D2020-04-13. 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 Serial Data Gateway Module X2 connector for terminal concerns and repair as needed.
PIP5700B2020-04-13. Service bulletin. ELECTRICAL SYSTEM; POWER TRAIN. This Preliminary information communicates to the dealer technician that the part numbers for the internal wiring harnesses for the 8 speed RWD transmissions are not listed in the Electronic Parts Catalog. Technicians are to refer to the information provided in this document to obtain the internal wiring harness part numbers by application.
PIT5287F2020-04-13. Service bulletin. EQUIPMENT:ELECTRICAL; ELECTRICAL SYSTEM. This Preliminary Information communication provides information to the technician with the correct way to remove the front shock electrical connector terminals. Technician will need to slightly bend the end of the J-38125-12A release tool. There is a purple Terminal Position Assurance that will align itself in the release position when the release tool is inserted into the release hole. There is a metal locking tab on the terminal that will need to be pushed in before the terminal will pull out of the connector.
DOR-E2P5T-032020-03-30. Service bulletin. VISIBILITY:POWER WINDOW DEVICES AND CONTROLS; ELECTRICAL SYSTEM. This SKU is a Power Window Regulator and Motor Assembly. The customer communication requested return of unsold inventory to inspect the software. The software may be too sensitive to the position of a locating magnet in the assembly causing the activation of the pinch point threshold prematurely. The window will stay open when it should have closed.

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