WenmarOpen by Wenmar Pro

Service bulletins for the 2014 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.

3324 on file from NHTSA, as of 2026-10-19.

By type

By component

By trouble code

By topic

Bulletins, newest first
PIP5189A2017-03-20. Service bulletin. ENGINE AND ENGINE COOLING:EXHAUST SYSTEM:EMISSION CONTROL:CATALYTIC CONVERTOR. THIS PRELIMINARY INFORMATION COMMUNICATION PROVIDES INFORMATION TO THE TECHNICIAN ABOUT VEHICLE THAT MAY HAVE BLACK SMOKE ON A COLD START. A DUAL-PULSE INJECTION STRATEGY IS UTILIZED DURING ENGINE COLD START TO REDUCE THE TIME REQUIRED TO BRING THE CATALYTIC CONVERTER UP TO OPERATING TEMPERATURE. THIS SPLIT INJECTION STRATEGY LASTS FOR ABOUT 60 SECONDS ON COLD START. THIS PROCESS MAY CAUSE THE CUSTOMER TO SEE INCREASED BLACK SMOKE DURING COLD START AND SHOULD BE CONSIDERED NORMAL.
PIP5130G2017-03-20. Service bulletin. FUEL SYSTEM, GASOLINE:FUEL INJECTION SYSTEM:FUEL RAIL; ENGINE. THIS PRELIMINARY INFORMATION COMMUNICATION PROVIDES INFORMATION TO THE TECHNICIAN HOW TO DIAGNOSE AND REPAIR A VEHICLE WITH AN ENGINE THAT RUNS WITH AN INTERMITTENT CRANK NO START WITH A DIAGNOSTIC TROUBLE CODE P0011 OR P00C6 CURRENT OR HISTORY. THE CAMSHAFT POSITION ACTUATOR SOLENOID VALVE MAY BE STICKING OR BINDING CAUSING THE VALVE TIMING TO BE RETARDED. DEALER WILL NEED TO CYCLE THE CAMSHAFT POSITION ACTUATOR SOLENOID VALVE BY ENERGIZING IT USING GLOBAL DIAGNOSTIC SYSTEM 2.
PIP5104B2017-03-20. Service bulletin. ENGINE. THIS PRELIMINARY INFORMATION COMMUNICATION PROVIDES INFORMATION TO THE TECHNICIAN ABOUT VEHICLES THAT MAY HAVE A COLD ENGINE TICK NOISE FOR 50 SECONDS AT START UP. TECHNICIAN DETERMINES IF THE TICK NOISE IS POSSIBLY COMING FROM THE EXHAUST MANIFOLD, AS THIS NOISE COULD EASILY BE MISTAKEN FOR AN ENGINE TICK NOISE. IF YOUR SI DIAGNOSIS DOES NOT ISOLATE THE CAUSE OF THIS CONCERN, THIS CONCERN SHOULD BE CONSIDERED A VEHICLE DESIGN CHARACTERISTIC OF THE ECM CALIBRATION AND NO ADDITIONAL REPAIRS SHOULD BE PERFORMED.
PIP4912D2017-03-20. Service bulletin. EQUIPMENT; ENGINE. THIS PRELIMINARY INFORMATION COMMUNICATION PROVIDES INFORMATION TO THE TECHNICIAN ON VEHICLES THAT MAY HAVE AN INTERMITTENT HIGH IDLE. IF A TECHNICIAN HAS DUPLICATED, OR THE CUSTOMER DESCRIPTION ALIGNS WITH THE SPEEDS MENTIONED IN THE IDLE SPEED DESCRIPTION TABLES, THE IDLE SPEED SHOULD BE CONSIDERED A NORMAL CHARACTERISTIC OF CURRENT VEHICLE DESIGN.
PIC61702017-03-17. Service bulletin. EQUIPMENT:ELECTRICAL:NAVIGATIONAL SYSTEM(GLOBAL POSITIONING SYSTEM). THIS PRELIMINARY INFORMATION COMMUNICATION PROVIDES INFORMATION TO THE TECHNICIAN WITH THE STEPS NEED TO DIAGNOSE AND REPAIR VEHICLE THAT MAY HAVE A CONCERN WITH NAVIGATION ICON NOT SHOWING THE CORRECT LOCATION THEN JUMPING TO THE CORRECT LOCATION. THE POSITION INDICATOR MAY SHOW THE VEHICLE TURNING IN THE OPPOSITE DIRECTION OR MAY SHOW THE VEHICLE TRAVELING OFF THE ROAD. TECHNICIAN WILL INSPECT THE HUMAN MACHINE INTERFACE MOUNTING. FOLLOW SERVICE INFORMATION FOR THE CORRECT ORIENTATION OF THE HUMAN MACHINE INTERFACE.
14-08-79-0012017-03-16. Service bulletin. EQUIPMENT. THIS INFORMATIONAL BULLETIN PROVIDES A LIST OF PARTS/REPLACEMENT PARTS FOR THE TONNEAU COVERS.
PIT53672017-03-16. Service bulletin. ELECTRICAL SYSTEM. THIS PRELIMINARY INFORMATION COMMUNICATION PROVIDES INFORMATION TO THE TECHNICIAN ABOUT VEHICLES THAT MAY HAVE A BLANK DISPLAYS, FLASHING DISPLAYS, “ERROR OR UPDATE FAILED MESSAGES”, NAVIGATION MAP NOT LOADING, BLUETOOTH OR USB CONCERNS. TECHNICIAN SHOULD INSPECT THE USB/SD CARD PORT FOR A SD CARD OR A DEVICE PLUG INTO ANY OF THE USB PORTS.
PIT5365A2017-03-16. Service bulletin. EQUIPMENT. THIS PRELIMINARY INFORMATION COMMUNICATION PROVIDES INFORMATION TO THE TECHNICIAN ON HOW THE RADIO DISPLAY GETS THE AIR AMBIENT TEMPERATURE. ON 1500 SERIES TRUCKS AND ALL SPORT UTILITY VEHICLE WITH REGULAR PRODUCTION OPTION CODE IO3 RADIO THE AMBIENT AIR TEMPERATURE SENSOR IS HARD WIRED TO THE ENGINE CONTROL MODULE AND THEN THE SIGNAL GOES ON HIGH SPEED LOCAL AREA NETWORK TO THE BODY CONTROL MODULE FROM THERE ON LOW SPEED LOCAL AREA NETWORK TO THE RADIO. ON 1500 SERIES TRUCKS AND ALL SPORT UTILITY VEHICLE WITH REGULAR PRODUCTION OPTION CODE IO4, IO5, OR IO6 THE AMBIENT AIR TEMPERATURE SENSOR IS HARD WIRED TO THE ENGINE CONTROL MODULE AND THEN THE SIGNAL GOES ON HIGH SPEED LOCAL AREA NETWORK TO THE BODY CONTROL MODULE FROM THERE ON LOW SPEED LOCAL AREA NETWORK TO THE RADIO THEN MOST 50 BUS TO THE HUMAN MACHINE INTERFACE. ON 2500/3500 SERIES TRUCKS PRODUCTION OPTION CODE IO3 RADIO THE AMBIENT AIR TEMPERATURE SENSOR IS HARD WIRED TO THE INSTRUMENT PANEL CLUSTER AND THEN THE SIGNAL GOES ON LOW SPEED LOCAL AREA NETWORK TO THE RADIO. ON 2500/3500 SERIES TRUCKS PRODUCTION OPTION CODE IO4, IO5, OR IO6 RADIO THE AMBIENT AIR TEMPERATURE SENSOR IS HARD WIRED TO THE INSTRUMENT PANEL CLUSTER AND THEN THE SIGNAL GOES ON LOW SPEED LOCAL AREA NETWORK TO THE RADIO THEN MOST 50 BUS TO THE HUMAN MACHINE INTERFACE.
PIT53652017-03-16. Service bulletin. EQUIPMENT. THIS PRELIMINARY INFORMATION COMMUNICATION PROVIDES INFORMATION TO THE TECHNICIAN ON HOW THE RADIO DISPLAY GETS THE AIR AMBIENT TEMPERATURE. ON 1500 SERIES TRUCKS AND ALL SPORT UTILITY VEHICLE WITH REGULAR PRODUCTION OPTION CODE IO3 RADIO THE AMBIENT AIR TEMPERATURE SENSOR IS HARD WIRED TO THE ENGINE CONTROL MODULE AND THEN THE SIGNAL GOES ON HIGH SPEED LOCAL AREA NETWORK TO THE BODY CONTROL MODULE FROM THERE ON LOW SPEED LOCAL AREA NETWORK TO THE RADIO. ON 1500 SERIES TRUCKS AND ALL SPORT UTILITY VEHICLE WITH REGULAR PRODUCTION OPTION CODE IO4, IO5, OR IO6 THE AMBIENT AIR TEMPERATURE SENSOR IS HARD WIRED TO THE ENGINE CONTROL MODULE AND THEN THE SIGNAL GOES ON HIGH SPEED LOCAL AREA NETWORK TO THE BODY CONTROL MODULE FROM THERE ON LOW SPEED LOCAL AREA NETWORK TO THE RADIO THEN MOST 50 BUS TO THE HUMAN MACHINE INTERFACE. ON 2500/3500 SERIES TRUCKS PRODUCTION OPTION CODE IO3 RADIO THE AMBIENT AIR TEMPERATURE SENSOR IS HARD WIRED TO THE INSTRUMENT PANEL CLUSTER AND THEN THE SIGNAL GOES ON LOW SPEED LOCAL AREA NETWORK TO THE RADIO. ON 2500/3500 SERIES TRUCKS PRODUCTION OPTION CODE IO4, IO5, OR IO6 RADIO THE AMBIENT AIR TEMPERATURE SENSOR IS HARD WIRED TO THE INSTRUMENT PANEL CLUSTER AND THEN THE SIGNAL GOES ON LOW SPEED LOCAL AREA NETWORK TO THE RADIO THEN MOST 50 BUS TO THE HUMAN MACHINE INTERFACE.
PIT5312A2017-03-16. Service bulletin. STEERING:COLUMN. THIS PRELIMINARY INFORMATION COMMUNICATION PROVIDES INFORMATION TO THE TECHNICIAN ON HOW TO DIAGNOSE AND REPAIR VEHICLES THAT MAY HAVE A GRIND, POP, SHUDDER OR BIND FEELING/NOISE IN THE STEERING COLUMN WHEN TURNING LEFT OR RIGHT. TECHNICIAN WILL INSPECT FOR THE LOWER COLUMN BEARING TO BE OUT OF POSITION AND THE UPPER INTERMEDIATE STEERING SHAFT TO LOWER COLUMN SHAFT BOLT AND NUT MAY BE CONTACTING THE INHIBITOR/SHIFTIER CABLE BRACKET. TECHNICIAN WILL REPLACE THE STEERING COLUMN FOR THIS CONCERN.
PIP52612017-03-16. Service bulletin. POWER TRAIN:TRANSFER CASE (4-WHEEL DRIVE); ELECTRICAL SYSTEM. THIS PRELIMINARY INFORMATION COMMUNICATION PROVIDES INFORMATION TO THE TECHNICIAN THAT SOME VEHICLES MAY HAVE A HIGH PITCHED WHINE NOISE FROM THE VEHICLE NOTICED WHEN DRIVING IN AUTO 4WD. WHEN THE TRANSFER CASE CONTROL MODULE HAS TO MOVE THE TRANSFER CASE ACTUATOR MOTOR THE HIGHER CURRENT PASSING THROUGH THE MODULE CAUSES AN "ELECTRONIC BUZZ OR WHINE" WITHIN SOME OF THE CAPACITORS IN THE MODULE THAT CAN BE HEARD BY SOME OF OUR CUSTOMERS. THIS CAN ONLY BE HEARD WITH ALL ACCESSORIES AND HVAC OFF AND ONLY WHEN ACTUATOR MOVEMENT IS REQUIRED. THIS DOES NOT INDICATE A CONCERN WITH THE MODULE AND SHOULD NOT BE REPLACED TO ADDRESS THIS CONCERN.
PIP52592017-03-16. Service bulletin. ENGINE. THIS PRELIMINARY INFORMATION COMMUNICATION PROVIDES INFORMATION TO THE TECHNICIAN ABOUT VEHICLES THAT MAY HAVE A SERVICE ENGINE SOON WITH DIAGNOSTIC TROUBLE CODE P0300 AND AN ENGINE MISFIRE. TECHNICIAN WILL NEED TO INSPECT THE VALVE OPERATION, IF THE VALVE OR VALVES ARE NOT MOVING THE ACTIVE FUEL MANAGEMENT LIFTERS AND GUIDE ON THE BANK WITH THE CONCERN AND THE OIL PUMP AND OIL PAN ASSEMBLY SHOULD BE REPLACED.
PIP5230A2017-03-15. Service bulletin. EQUIPMENT. THIS PRELIMINARY INFORMATION COMMUNICATION ADVISES THE TECHNICIAN BEFORE REPLACING THE CRANKSHAFT TO REVIEW THE FOLLOWING. DEALER SHOULD COMPLETE THE SERVICE INFORMATION DIAGNOSTICS AND THE COST COMPARISON WORKSHEET FOR ASSEMBLY REPAIR VS REPLACEMENT. TECHNICIAN WILL USE THE LATEST VERSION OF 09-06-04-026G TO VERIFY THE ECM CALIBRATION IS NOT AN AFTERMARKET CALIBRATION. IF THE CUSTOMER PREFERS TO KEEP THE ORIGINAL NUMBERS MATCHING ENGINE PLEASE CALL TAC FOR REPAIR DIRECTION.
PIP5204E2017-03-15. Service bulletin. EQUIPMENT. THIS PRELIMINARY INFORMATION COMMUNICATION ADVISES THE TECHNICIAN THE DIESEL OXIDATION CONVERTER PART RESTRICTION HAS ENDED. DEALER CAN NOW ORDER THE PARTS THROUGH THE REGULAR CUSTOMER CARE AND AFTERSALES PARTS PROCESS.
PIP4568R2017-03-14. Service bulletin. POWER TRAIN:AUTOMATIC TRANSMISSION; ENGINE; EQUIPMENT ADAPTIVE/MOBILITY. THIS PRELIMINARY INFORMATION COMMUNICATION PROVIDES INFORMATION TO THE TECHNICIAN THAT SOME VEHICLES MAY HAVE A SERVICE ENGINE SOON LAMP, ENGINE MISFIRE ON CYLINDER 1, 4, 6, OR 7 AND/OR TICK NOISE. TECHNICIAN WILL FOLLOW SERVICE INFORMATION DIAGNOSIS FIRST. IF SERVICE INFORMATION DIAGNOSIS DOES NOT ISOLATE THE CAUSE OF THIS CONCERN PERFORM A CYLINDER DEACTIVATION ACTIVE FUEL MANAGEMENT SYSTEM COMPRESSION TEST IN SERVICE INFORMATION. IF THE RUNNING COMPRESSION OF THE MISFIRING CYLINDER STAYS BELOW 25 POUNDS PER SQUARE INCH REGARDLESS OF THE ACTIVE FUEL MANAGEMENT SOLENOID BEING COMMANDED ON OR OFF, AN ACTIVE FUEL MANAGEMENT LIFTER IS MECHANICALLY COLLAPSED/STUCK OR UNLOCKING AS SOON AS THE ENGINE IS STARTED. REPLACE ALL ACTIVE FUEL MANAGEMENT LIFTERS, AND ALL PLASTIC LIFTER GUIDES. ALSO PERFORM THE CYLINDER DEACTIVATION ACTIVE FUEL MANAGEMENT VALVE LIFTER OIL MANIFOLD DIAGNOSIS AND TESTING IN SERVICE INFORMATION. IF IT ISOLATES A CONCERN WITH THE VALVE LIFTER OIL MANIFOLD, REPLACE IT AND REEVALUATE THE CONCERN. THE ACTIVE FUEL MANAGEMENT LIFTERS CAN ALSO BE MONITORED FOR PROPER OPERATION BY CAREFULLY INSPECTING THE CYLINDER 1, 4, 6, AND 7 ROCKERS AND VALVES WHILE CRANKING OR BRIEFLY AND SAFELY RUNNING THE ENGINE WITH THE VALVE COVERS REMOVED. IF THE VALVE OR VALVES OF AN ACTIVE FUEL MANAGEMENT CYLINDER STOP MOVING WHILE DOING THIS TEST, THE ACTIVE FUEL MANAGEMENT LIFTER IS CAUSING THE CONCERN. FOR 2008-2009 FULL SIZE TRUCK/SUV OR A 2007-2009 CHEVROLET TAHOE WITH THE POLICE PACKAGE REPROGRAM THE ENGINE CONTROL MODULE. ON THE 2008-2009 PONTIAC G8, 2010-2011 CAMARO, AND 2007-2010 FULL SIZE TRUCKS WITH ACTIVE FUEL MANAGEMENT, ALSO DETERMINE IF THE ACTIVE FUEL MANAGEMENT PRESSURE RELIEF VALVE SHIELD THAT IS LISTED IN THE LATEST VERSION OF 10-06-01-008 HAS EVER BEEN INSTALLED. ON PASSENGER CARS WITH THE LS4 ENGINE, DETERMINE IF THE UPDATED OIL PAN GASKET THAT IS LISTED IN THE LATEST VERSION OF 11-06-01-007 HAS BEEN INSTALLED.
PIC3278F2017-03-14. Service bulletin. EQUIPMENT:ELECTRICAL; ELECTRICAL SYSTEM. THIS PRELIMINARY INFORMATION COMMUNICATION PROVIDES INFORMATION TO THE TECHNICIAN THE STEPS NEEDED TO DIAGNOSE AND REPAIR THE VEHICLES THAT MAY HAVE UNWANTED OR PHANTOM PHONE CALLS. TECHNICIAN WILL NEED TO DETERMINE WHAT TYPE OF CALL THE CUSTOMER IS HAVING THAT IS UNWANTED. THE VEHICLE MAY RECEIVE AN INCOMING CALL JUST LIKE ANY OTHER PHONE. TYPICALLY THE CUSTOMER WILL HEAR THE PHONE RINGING IN THE VEHICLE. THIS SCENARIO ALSO INCLUDES INCOMING BLUETOOTH CALLS. ONE TYPE OF UNWANTED CALL CAN BE MADE IF THE KEY PAD IS FAULTY THE ONSTAR SYSTEM WILL TRY TO MAKE A BLUE BUTTON CALL FOR SHORTED VOLTAGE IN THE CIRCUITS. THE ONSTAR MODULE COULD HAVE AN INTERNAL FAULT AND PRODUCE A PHONE UNAVAILABLE AUDIO MESSAGE ALSO IT MAY HAVE A DIAGNOSTIC TROUBLE CODE U1500 OR B1000. REFER TO DIAGNOSTICS FOR THE DIAGNOSTIC TROUBLE CODE MAKING SURE TO FOLLOW ANY APPLICABLE BULLETINS OR PRELIMINARY INFORMATION SHEETS. A GREADYH OR GONSTAR READYH AUDIO MESSAGE HEARD WHILE DRIVING. IN SOME CASES IT HAS BEEN FOUND THAT THE CUSTOMER IS INADVERTENTLY PRESSING THE PUSH TO TALK BUTTON ON THE STEERING WHEEL CONTROLS. ON RARE OCCASIONS, OTHER ISSUES IN THE STEERING COLUMN OR STEERING WHEEL CONTROL SYSTEM MAY INDUCE THIS CONCERN.
PI0652A2017-03-14. Service bulletin. EQUIPMENT. THIS PRELIMINARY BULLETIN PROVIDES A INFORMATION ON HOW TO REMOVE THE SEIZED TEMPERATURE SENSORS FROM THE DPF.
PI1354D2017-03-13. Service bulletin. STEERING:HYDRAULIC POWER ASSIST:POWER STEERING FLUID; ELECTRICAL SYSTEM; SUSPENSION. THIS PRELIMINARY INFORMATIONAL BULLETIN PROVIDES INFORMATION ON A PROCEDURE FOR DIAGNOSING AND REPAIRING VIBRATIONS CAUSED BY THE WHEEL AND TIRE, AXLE COMPONENTS AND/OR PROPELLER SHAFTS.
PI1288A2017-03-09. Service bulletin. EQUIPMENT:ELECTRICAL:RADIO/TAPE DECK/CD ETC.. THIS PRELIMINARY BULLETIN PROVIDES A PROCEDURE TO REPROGRAM THE RADIO TO CORRECT THE CUSTOMERS CONCERN OF POOR RADIO RECEPTION.
G-1990412017-03-03. Service bulletin. FUEL SYSTEM, GASOLINE:DELIVERY:FUEL PUMP. 14289 - SPECIAL COVERAGE. ON SOME VEHICLES, EQUIPPED WITH E85 FLEX FUEL CAPABILITY (FHS), THE FLEXIBLE FUEL SENSOR MAY BECOME INOPERATIVE DURING NORMAL OPERATION DUE TO AN ELECTRICAL FAILURE CAUSED BY ROAD SALT AND OTHER ENVIRONMENTAL CONTAMINANTS. WITH A FAULTY FLEX FUEL SENSOR, THE SERVICE ENGINE SOON LIGHT WILL ILLUMINATE AND REMOTE START WILL BE INOPERATIVE. DEALERS ARE TO REPLACE THE FUEL FLEX SENSOR. THE REPAIRS WILL BE MADE AT NO CHARGE TO THE CUSTOMER.
14166-A2017-03-03. Service bulletin. AIR BAGS. 14166A - CUSTOMER SATISFACTION (REVISED NET ITEM ALLOWANCE). CERTAIN VEHICLES HAVE DRIVER AND PASSENGER SEAT SIDE IMPACT AIRBAG (SIAB) WIRING HARNESS CONNECTORS THAT MAY HAVE HIGH RESISTANCE. THE VEHICLE SENSING AND DIAGNOSTIC MODULE (SDM) INTERPRETS THE HIGH RESISTANCE AS A FAULT. A FAULT WILL ILLUMINATE THE AIRBAG READINESS LIGHT AND TURN ON A “SERVICE AIR BAG” DRIVER INFORMATION CENTER (DIC) MESSAGE. THE FAULT AND THE WARNING INDICATORS MAY BE INTERMITTENT. DEPENDING ON THE LEVEL OF RESISTANCE, THE SIABS MAY NOT DEPLOY IN A CRASH. REMOVE THE DRIVER AND PASSENGER SIAB WIRING HARNESS CONNECTORS AND INSTALL ELECTRICAL JUMPER WIRES IN THEIR PLACE.
G-1978282017-03-03. Service bulletin. EQUIPMENT. 14151 - CUSTOMER SATISFACTION (MESSAGE ONLY, VIN LIST WAS NOT ATTACHED TO THE PREVIOUS MESSAGE). THIS MESSAGE IS TO ALERT DEALERS THAT GENERAL MOTORS HAS BECOME AWARE THAT SOME CUSTOMERS MAY BE OVERFILLING THEIR COMPRESSED NATURAL GAS (CNG) TANKS IN COLD WEATHER BY ADDING CNG BEYOND THE RECOMMENDED FILL PRESSURE. IF CNG TANKS ARE FILLED TO A HIGHER PRESSURE THAN RECOMMENDED AT A GIVEN AMBIENT TEMPERATURE, THEN MOVED TO A MUCH HIGHER AMBIENT TEMPERATURE ENVIRONMENT, EXPANSION OF THE GAS CAUSED BY THE TEMPERATURE CHANGE MAY CAUSE PRESSURE RELIEF DEVICES ON THE VEHICLE CNG TANK(S) TO RELEASE GAS, AS DESIGNED. IF AN IGNITION SOURCE WERE PRESENT, THIS COULD CREATE A RISK OF FIRE OR EXPLOSION. AN ADVISORY LETTER WAS MAILED TO ALL INVOLVED CUSTOMERS ALONG WITH AND OWNER MANUAL CNG SUPPLEMENT AND TWO LABELS WITH INSTRUCTIONS.
G-1977352017-03-03. Service bulletin. EQUIPMENT. 14151 - CUSTOMER SATISFACTION (MESSAGE ONLY WITH LETTER). THIS MESSAGE IS TO ALERT DEALERS THAT GENERAL MOTORS HAS BECOME AWARE THAT SOME CUSTOMERS MAY BE OVERFILLING THEIR COMPRESSED NATURAL GAS (CNG) TANKS IN COLD WEATHER BY ADDING CNG BEYOND THE RECOMMENDED FILL PRESSURE. IF CNG TANKS ARE FILLED TO A HIGHER PRESSURE THAN RECOMMENDED AT A GIVEN AMBIENT TEMPERATURE, THEN MOVED TO A MUCH HIGHER AMBIENT TEMPERATURE ENVIRONMENT, EXPANSION OF THE GAS CAUSED BY THE TEMPERATURE CHANGE MAY CAUSE PRESSURE RELIEF DEVICES ON THE VEHICLE CNG TANK(S) TO RELEASE GAS, AS DESIGNED. IF AN IGNITION SOURCE WERE PRESENT, THIS COULD CREATE A RISK OF FIRE OR EXPLOSION. AN ADVISORY LETTER WAS MAILED TO ALL INVOLVED CUSTOMERS ALONG WITH AND OWNER MANUAL CNG SUPPLEMENT AND TWO LABELS WITH INSTRUCTIONS.
G-1947842017-02-24. Service bulletin. ELECTRICAL SYSTEM: INSTRUMENT CLUSTER/PANEL. 14126 - SERVICE UPDATE. THIS BULLETIN PROVIDES A SERVICE PROCEDURE TO REPROGRAM THE INSTRUMENT PANEL CLUSTER ON CERTAIN VEHICLES. ALSO INVOLVED ARE CERTAIN 2015 MY CHEVROLET SUBURBAN, TAHOE AND GMC YUKON VEHICLES. THESE VEHICLES MAY HAVE AN ODOMETER READING AT “PEEK IN” (I.E. DRIVER INFORMATION CENTER (DIC) SCREEN WHEN THE VEHICLE IS IN THE OFF POWER MODE BUT THE CLUSTER IS AWAKENED BY OPENING THE CAR DOOR OR USING THE KEY FOB) DOES NOT MATCH THE SEASON ODOMETER READING WHEN THE VEHICLE IS IN THE RUN POWER MODE. THE TRIP A/B AND FUEL ECONOMY DISPLAYS MAY ALSO BE INCORRECT. THIS CONDITION OCCURS, WHEN THE VEHICLE SITS FOR AN EXTENDED PERIOD OF TIME AND, NORMAL PARASITIC CURRENT DRAWS DEPLETE THE BATTERY STATE OF CHARGE TO LESS THAN 12 VOLTS AND, THE VEHICLE IS IN THE OFF POWER MODE WHEN THE CLUSTER IS AWAKENED AS DESCRIBED ABOVE.
G-1933602017-02-23. Service bulletin. EQUIPMENT:OTHER:OWNERS/SERVICE/OTHER MANUAL. 14212 - CUSTOMER SATISFACTION. CERTAIN VEHICLES MAY HAVE INACCURATE TOWING CAPACITY VALUES REPORTED IN THE OWNER’S MANUAL. USE OF HIGHER THAN RECOMMENDED MAXIMUM TRAILER WEIGHT COULD RESULT IN A POWERTRAIN COOLING SYSTEM OVERHEAT CONDITION IF OPERATING THE VEHICLE UNDER CERTAIN HIGH AMBIENT TEMPERATURE AND ROAD GRADE CONDITIONS. DEALERS ARE TO PLACE A COPY OF AN UPDATED TOWING CAPACITY TABLE SUPPLEMENT IN THE OWNER MANUAL. GM WILL MAIL THE SUPPLEMENT TO CUSTOMERS OF RECORD.

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