2004 Chevrolet Trailblazer

The subject vehicles are model year (MY) 2002-2009 Chevrolet Trailblazer, GMC Envoy, 2004-2007 Buick Rainier, 2003-2008 Isuzu Ascender, 2005-2009 Saab 9-7X, 2002-2004 Oldsmobile Bravada, 2003-2006 Chevrolet SSR, 2005-2009 Buick Lacrosse, and 2006-2008 Pontiac Grand Prix. This scope includes the Trailblazer/Envoy variants: 2002-2006 Envoy XL/Trailblazer EXT and 2004-2005 Envoy XUV. The original scope of this investigation was expanded to include all vehicles equipped with the subject Headlight Driver Module (HDM). The focus of the investigation was to determine whether actions performed by General Motors adequately addressed any unreasonable risk to motor vehicle safety in the subject vehicles concerning the headlights and the HDM that controls them.Under normal electrical load and environmental conditions, the HDM can overheat inside the Underhood Electrical Center (UEC). This can cause the module to fail and result in a simultaneous loss of both low beam headlights and both daytime running lights (DRLs), often with no warning or prior detectability to the driver. This failure can be intermittent or permanent. No other exterior lights are affected. High beams, turn signals, brake lights, and reverse lights are still operational.General Motors addressed this issue with 2 recalls (14V755 & 15V519) and a special coverage program (N172091910). In view of the recalls and special coverage program implemented by GM and the vehicle high beams continuing to operate, ODI has tentatively concluded that the actions taken by GM mitigate any unreasonable risk to safety posed by HDM failure in the subject vehicles.Accordingly, the investigation is closed. The closing of this investigation does not constitute a finding by NHTSA that a safety-related defect does not exist. The agency reserves the right to take additional action if warranted by new circumstances.The ODI reports cited above are available for review online at NHTSA.gov under the identification numbers in the attached document.

DURING THE COURSE OF THIS EA INVESTIGATION, ODI OBSERVED THAT THE MAJORITY OF THE COMPLAINTS (88%) AND WARRANTY CLAIMS (94%) WERE REPORTED FOR VEHICLES THAT ARE REGISTERED FOR USE IN THE SALT BELT REGION OF THE US.THIS AREA INCLUDES 20 STATES IN THE NORTHEAST, MID ATLANTIC AND THE MIDWEST REGIONS AND THE DISTRICT OF COLUMBIA.CONSUMERS IN THE SALT BELT REGION REPORTED TO ODI THAT THEY COULD SMELL FUEL VAPORS IN THEIR VEHICLES WHILE DRIVING.UPON FURTHER EXAMINATION OF THEIR VEHICLES, THEY DISCOVERED THAT FUEL VAPORS WERE COMING OUT OF THE TOP OF THE FUEL TANK. THIS CONDITION IS CAUSED BY CORROSION OF THE RETURN AND SENDER LINES OF THE FUEL PUMP MODULE.WATER AND ROAD SALT COLLECT ON TOP OF THE FUEL PUMP LEADING TO SMALL PINHOLES APPEARING ON THE FUEL LINES.FUEL MAY LEAK AND COLLECT ON TOP OF THE MODULE AND/OR SPILL ONTO THE GROUND.THE DATA EVALUATED UNDER THIS INVESTIGATION REFLECT A RELATIVELY LOW FREQUENCY OF OCCURRENCE THAT LARGELY ARISES IN SALT BELT STATES.GM HAS EXTENDED THE WARRANTY ON THE SUBJECT COMPONENT TO TEN YEARS OR 120,000 MILES.FURTHER USE OF AGENCY RESOURCES DOES NOT APPEAR TO BE WARRANTED AT THIS TIME; ACCORDINGLY, THIS INVESTIGATION IS CLOSED.THE CLOSING OF THIS INVESTIGATION DOES NOT CONSTITUTE A FINDING BY NHTSA THAT NO SAFETY-RELATED DEFECT EXISTS.THE AGENCY RESERVES THE RIGHT TO TAKE FURTHER ACTION IF WARRANTED BY THE CIRCUMSTANCES.FOR ADDITIONAL INFORMATION SELECT DOCUMENT SEARCH.

GM STATES THAT SOME BRAKE/TAIL LAMP BULBS CAN PREMATURELY BECOME INOPERATIVE DUE TO MALFUNCTIONING BRAKE/TAIL LAMP SOCKETS.ON MARCH 2, 2004, GM INITIATED A 6-YEAR/72,000 MILE SPECIAL POLICY FOR 989,487 SUBJECT VEHICLES TO INSPECT AND REPLACE THE REAR BRAKE/TAIL LAMP BULB SOCKET ASSEMBLIES.ON APRIL 4, 2004, THE OFFICE OF DEFECTS INVESTIGATION (ODI) OPENED A PRELIMINARY EVALUATION (PE04-032) BASED ON CONSUMER COMPLAINTS ALLEGING BRAKE LIGHTS NOT OPERATING WHEN THE BRAKE PEDAL IS DEPRESSED.ON AUGUST 3, 2004 ODI UPGRADED PE04-032 TO AN ENGINEERING ANALYSIS (EA04-021).BY LETTER DATED OCTOBER 27, 2004 GM NOTIFIED NHTSA THAT IT WILL CONDUCT A SAFETY RECALL (NHTSA # 04V527) COVERING SUBJECT VEHICLES THAT WERE NOT ALREADY REPAIRED UNDER GM'S SPECIAL POLICY.MY 2004 SUBJECT VEHICLES BUILT AFTER AUGUST 8, 2003 CONTAIN IMPROVED BRAKE LAMP ASSEMBLIES AND ARE NOT INCLUDED IN THE RECALL.GM DEALERS WILL INSTALL THE IMPROVED BRAKE LAMP ASSEMBLY ON SUBJECT VEHICLES BUILT ON AUGUST 8, 2003 AND EARLIER.THE ACTION TAKEN BY GM IS SUFFICIENT TO RESOLVE THE ISSUES RAISED BY THIS INVESTIGATION.ACCORDINGLY, THIS INVESTIGATION IS CLOSED.

THE OFFICE OF DEFECTS INVESTIGATION (ODI) OPENED THIS INVESTIGATION ON MODEL YEAR (MY) 2002-04 CHEVROLET TRAILBLAZER VEHICLES.GM REPORTS THAT OTHER VEHICLES SHARING THIS PLATFORM AND BRAKE LAMP DESIGN ARE THE MY 2002-2004 CHEVROLET TRAILBLAZER EXT; GMC ENVOY, XL, XUV; OLDSMOBILE BRAVADA AND 2004 BUICK RAINIER.COMPLAINTS ALLEGE THAT THE REAR BRAKE LAMP DOES NOT OPERATE WHEN THE BRAKE PEDAL IS DEPRESSED.THERE IS NO INDICATION TO THE DRIVER FROM INSIDE THE VEHICLE THAT ONE OR MORE BRAKE LAMPS BULBS ARE NOT FUNCTIONING.GM FOUND THAT HEAT FROM THE BULB COULD DEFORM THE LAMP SOCKET, PRODUCE ELECTRICAL ARCING AND AN INOPERATIVE BULB.TO CORRECT THE CONDITION, GM CHANGED THE BULB TO A BULB THAT TRANSMITS LESS HEAT TO THE SOCKET AND CHANGED THE SOCKET TO A THERMOPLASTIC POLYMER TO IMPROVE THERMAL STABILITY.THESE CHANGES WERE IMPLEMENTED INTO PRODUCTION VEHICLES ON OCTOBER 1, 2003.GM IMPLEMENTED A SPECIAL POLICY BY NOTIFYING CONSUMERS THAT IF THEY SHOULD EXPERIENCE A BRAKE LAMP FAILURE TO GO TO THEIR GM DEALERSHIP TO HAVE THE CIRCUIT BOARD CONTAINING THE BRAKE LAMP REPLACED ALONG WITH NEW BULBS.THIS POLICY IS GOOD FOR THE FIRST 6 YEARS OR 72,000 MILES OF THE LIFE OF THE VEHICLE.ODI WILL UPGRADE THIS INVESTIGATION TO EA 04-021 AND INCLUDE THE ABOVE MENTIONED VEHICLES.

I was driving and a girl pulled out from a stop sign and hit my passenger side front of my trailblazer. Her airbags deployed immediately, meanwhile mine didn't deploy. My husband saved my face by throwing his arm over me!

NHTSA ID

11679602

Incident

Aug 9, 2025

The contact owns a 2004 Chevrolet Trailblazer. The contact stated while driving at various speeds, the headlights became inoperable. After a while, the headlights became operational. There were no warning lights illuminated. The local dealer was not contacted. The vehicle was not diagnosed or repaired. The manufacturer was not contacted. The approximate failure mileage was 189,000.

NHTSA ID

11483548

Incident

Mar 1, 2022

Mileage

189,000 mi

Electronic throttle body? No throttle control, motor will only idle, turn ignition switch off, then restart it will run. Reduced Engine Power light comes on. Happens for no apparent reason. Very unsafe situation.

NHTSA ID

11446505

Incident

Jan 1, 2021

The contact owned a 2004 Chevrolet Trailblazer. The contact stated that while driving at an undisclosed speed, there was smoke coming from the rear passenger side. The contact pulled over and noticed that underneath the rear passenger's seat had caught fire. The fire department was able to extinguish the fire. The contact sustained burns to his left shoulder, hands, and elbows. However, no medical treatment was received. A police report was filed. The contact was unaware if there was a fire department report. The vehicle was towed to a tow yard and deemed totaled by the insurance company. The manufacturer was not made aware of the failure. The failure mileage was approximately 153,000. Vehicle caught on fire on the inside driving.

NHTSA ID

11446470

Incident

Jan 4, 2022

Mileage

153,000 mi

The contact owns a 2004 Chevrolet Trailblazer equipped with Hankook tires Model:Dynapro HT Tire Size: P245/70R16 Dot Number:Unknown. The contact stated that she had both rear tires, driver side and passenger side, replaced with the Hankook tires by an independent mechanic. After the instillation, the contact stated that the vehicle would shake while driving at various speeds without warning . The vehicle was taken to another independent mechanic who inspected the tires and made adjustments; however, the shaking persisted. While driving at 65 MPH, the lost control of the vehicle's steering as the vehicle began to abruptly fishtail. As the vehicle continued to spin out of control, the contact was able to stop the vehicle moments before the vehicle hit a highway barrier. The contact discovered that the rear driver side tire tread had separated from the rim of tire. Due to the failure, the contact had the tire replaced with a spare and was able to drive the vehicle home. The contact called the place where the tires were purchased; they offered no assistance and stated they were no responsible for the failure. The manufacturer had yet to be notified of the failure. The vehicle had yet to be repaired. The tire failure mileage was approximately 1,700. The vehicle failure mileage was approximately 89,000.

NHTSA ID

11442866

Incident

Dec 4, 2021

Mileage

89,000 mi

FUL PUMP

NHTSA ID

11414718

Incident

Apr 3, 2021

Mileage

35 mi

MY CLUSTERBOARD IS COMPLETELY NON FUNCTIONING THE READINGS ARE NOT WORKING

NHTSA ID

11386667

Incident

Jul 19, 2019

TL* THE CONTACT OWNS A 2004 CHEVROLET TRAILBLAZER. THE CONTACT STATED THE HE NOTICED A FUEL ODOR EMITTING FROM UNDERNEATH THE DRIVER'S SIDE OF THE VEHICLE. THE CONTACT ALSO STATED THAT THE FUEL MILEAGE HAD ALSO DECREASED WHEN DRIVING THE VEHICLE. THE CONTACT TOOK THE VEHICLE TO HAVE AN EVAP SMOKE TEST PERFORMED ON HIS VEHICLE. THE RESULT OF THE TEST DISCOVERED THAT A CRACK HAD FORMED ON THE FUEL NECK THAT CONNECTS TO THE FUEL TANK, WHICH WAS THE CAUSE OF THE FAILURE. THE CONTACT THEN SPOKE WITH J.B.A. CHEVROLET (7327 RITCHIE HWY, GLEN BURNIE, MD 21061) WHERE HE WAS INFORMED THAT THERE WERE NO RECALLS ON THE VEHICLE FOR THE FAILURE. THE MANUFACTURER WAS NOTIFIED OF THE FAILURE. THE VEHICLE WAS NOT REPAIRED. THE FAILURE MILEAGE WAS APPROXIMATELY 126,432.

NHTSA ID

11350043

Incident

Jul 28, 2020

Mileage

126,432 mi

This PI communicates the requirement to provide a pico file to receive diagnostic assistance from TAC.

This Preliminary Information communication provides information to the technician about vehicles that have an unusual noise and is difficult to identify, isolate or pinpoint. Technician should get record a sound clip or take a video of the noise for assessment by engineering. Technician will need to call General Motors Technical Assistance Center for further assistance.

This Preliminary Information communicates to the dealer the process for downloading or updating operating software for the Tire Pressure Monitor, Active Fuel Injector tester, multi media tester, PICO Scope, GR8 starting/charging tester  and Vehicle Data Recorder tools, giving website address and step by step instructions to complete the update.

This Preliminary Information communication provides information to the technician about vehicles that the Heater-Vent-Air Conditioning blows warm air. Before calling General Motors Technical Assistance Center technician will need to have high and low pressures, outside temperature, humidity, and vent temperature.

This Preliminary Information communication provides information to the technician about vehicles that the Heater-Vent-Air Conditioning blows warm air. Before calling General Motors Technical Assistance Center technician will need to have high and low pressures, outside temperature, humidity, and vent temperature.

This Preliminary Information communication provides information to the technician about changing the tire and wheel size on vehicles. General Motors will only support a tire calibration for tires that have been sized, tested and designed for the vehicle in question and its applications. Technician should not use the information that is provided by the antilock braking system tire size selection.