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2004 Chevrolet Trailblazer

Owner reports · Recalls · Investigations

More warning signs than most Trailblazer years

Owner complaints for the 2004 Chevrolet Trailblazer are substantially higher than the model-year median of 87.5.

About this comparison →

When problems were reported

Mileage at the reported incident

899 reports with mileage · 182 unknown

NHTSA’s mileage field refers to the reported incident, not necessarily the filing date. This shows report counts, not the likelihood of a failure.

What to inspect

Issues worth paying extra attention to based on owner reports.

  • Electrical System. Review the 627 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
  • Exterior Lighting. Review the 101 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
  • Fuel System, Gasoline. Review the 93 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →

NHTSA owner reports · September 18, 2026 snapshot.

56 crash reports31 fire reports47 injury reports

What owners actually said

1,081 reports
53,000 miles · Jun 6, 2012
Engine

TL* THE CONTACT OWNS A 2004 CHEVROLET TRAILBLAZER. WHILE PARKED WITH THE ENGINE RUNNING, THE CONTACT HEARD A LOUD KNOCKING NOISE COMING FROM THE ENGINE. THE VEHICLE WAS TAKEN TO THE DEALER FOR DIAGNOSTICS. THE TECHNICIAN ADVISED THAT THE KNOCKING NOISE WAS NORMAL FOR THE TYPE OF ENGINE IN THE VEHICLE. THE VEHICLE WAS THEN TAKEN …

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TL* THE CONTACT OWNS A 2004 CHEVROLET TRAILBLAZER. WHILE PARKED WITH THE ENGINE RUNNING, THE CONTACT HEARD A LOUD KNOCKING NOISE COMING FROM THE ENGINE. THE VEHICLE WAS TAKEN TO THE DEALER FOR DIAGNOSTICS. THE TECHNICIAN ADVISED THAT THE KNOCKING NOISE WAS NORMAL FOR THE TYPE OF ENGINE IN THE VEHICLE. THE VEHICLE WAS THEN TAKEN TO AN INDEPENDENT MECHANIC WHO ADVISED THE CONTACT THAT THE PISTONS IN THE ENGINE WERE DOWN SIZED, CAUSING THE NOISE. THE VEHICLE WAS NOT REPAIRED. THE APPROXIMATE FAILURE MILEAGE WAS 53,000.

NHTSA ODI #10460795

79,548 miles · Jun 5, 2012
Electrical SystemElectronic Stability Control (esc)

I HAVE A 2004 CHEVY TRAILBLAZER AND THE CLUSTER IS GOING BAD . FINDING OUT THAT I'M NOT THE ONLY ONE THAT HAS THIS PROBLEM . I HAD THE SAME PROBLEM WITH MY CHEVY AVALANCHE AND IT WAS RECALLED . I THINK THAT THIS A PROBLEM WHILE DRIVING . I THINK SOMEONE SHOULD DO SOMETHING BEFORE SOMEONE GETS HURT. BECAUSE THE GAUGES GO OUT THE …

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I HAVE A 2004 CHEVY TRAILBLAZER AND THE CLUSTER IS GOING BAD . FINDING OUT THAT I'M NOT THE ONLY ONE THAT HAS THIS PROBLEM . I HAD THE SAME PROBLEM WITH MY CHEVY AVALANCHE AND IT WAS RECALLED . I THINK THAT THIS A PROBLEM WHILE DRIVING . I THINK SOMEONE SHOULD DO SOMETHING BEFORE SOMEONE GETS HURT. BECAUSE THE GAUGES GO OUT THE ON AND WHILE DRIVING. IT COULD HURT A YOUNG DRIVER THAT DOESN'T WHAT TO DO. GM KNOWS THE PROBLEM BUT WILL NOT DO ANYTHING ABOUT IT . IT THE SAME PROBLEM THAT THEY DID A RECALL ON WITH THE TRUCKS. SO I THINK THEY SHOULD FIX THIS PROBLEM. SO COULD YOU PLEASE HELP BEFORE SOMEONE GETS HURT BAD OVER THIS PROBLEM. THANK YOU PLEASE HELP! *TR

NHTSA ODI #10460617

76,000 miles · Jun 4, 2012
Fuel/propulsion System

WAS SMELLING GAS INSIDE AND OUTSIDE OF CAR. UPON INSPECTION DISCOVERED THE GAS TANK IS LEAKING. READING RECALLS DISCOVERED GM IS ONLY REPLACING TANKS ON VEHICLES MADE AT CERTAIN FACTORIES AND ONLY IN CERTAIN GEOGRAPHICAL AREAS. WITH THE AMOUNT OF VEHICLES AFFECTED GM SHOULD HAVE TO REPLACE THEM ALL WITHOUT DISCRIMINATION. THIS V…

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WAS SMELLING GAS INSIDE AND OUTSIDE OF CAR. UPON INSPECTION DISCOVERED THE GAS TANK IS LEAKING. READING RECALLS DISCOVERED GM IS ONLY REPLACING TANKS ON VEHICLES MADE AT CERTAIN FACTORIES AND ONLY IN CERTAIN GEOGRAPHICAL AREAS. WITH THE AMOUNT OF VEHICLES AFFECTED GM SHOULD HAVE TO REPLACE THEM ALL WITHOUT DISCRIMINATION. THIS VEHICLE HAS BEEN NOTHING BUT A MONEY PIT FOR ME AND HAS BEEN THE WORSE CAR I EVER OWNED BASED ON REPAIRS REQUIRED TO KEEP IT GOING. *TR

NHTSA ODI #10460517

70,000 miles · May 25, 2012
Electrical System

THIS ISSUE NEEDS TO BE ADDRESSED, MY SPEEDOMETER AND TRANS METER ON LEFT OF SPEEDOMETER STARTED SHOWING MY CHEVROLET SPEED WAS 80 MILES AN HOUR EVEN IN PARK. THEN WHILE I DRIVE IT WILL MOVE TO 100 MILES AN HOUR WHILE I'M DRIVING 35, AND IT MOVES UP AND DOWN DEPENDING ON MY SPEED. SOME TIMES IT WILL WORK OTHER TIMES IT WILL NOT …

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THIS ISSUE NEEDS TO BE ADDRESSED, MY SPEEDOMETER AND TRANS METER ON LEFT OF SPEEDOMETER STARTED SHOWING MY CHEVROLET SPEED WAS 80 MILES AN HOUR EVEN IN PARK. THEN WHILE I DRIVE IT WILL MOVE TO 100 MILES AN HOUR WHILE I'M DRIVING 35, AND IT MOVES UP AND DOWN DEPENDING ON MY SPEED. SOME TIMES IT WILL WORK OTHER TIMES IT WILL NOT SHOW THE CORRECT SPEED, OR ACCELERATION ON TRANS METER TO THE LEFT OF SPEEDOMETER. I HAVE WENT ONLINE AND SEEN 1000'S OF PEOPLE SAYING THE SAME THING AT THE SAME MILES OF THE CHEVROLET. 70,000-90,000 MOST ARE AROUND 80,000. SHOULDN'T THIS HAVE BEEN RECALLED YEARS AGO? AND WHY HAVE THIS ISSUE BEEN IGNORED FOR SO LONG? *TR

NHTSA ODI #10459640

51,590 miles · Apr 30, 2012
Tires

TL* THE CONTACT OWNS A 2004 CHEVROLET TRAILBLAZER LT EQUIPPED WITH CONTINENTAL CONTITRAC TR TIRES (SIZE:P245/65R17) THAT WERE USED ON THE FRONT AND REAR. THE CONTACT STATED THAT THE SIDE WALLS HAD BECOME SEPARATED FROM THE TIRE. PRIOR TO THE FAILURE, THE CONTACT NOTICED THAT AN ABNORMAL WOBBLE NOISE WAS BEING EMITTED FROM THE TI…

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TL* THE CONTACT OWNS A 2004 CHEVROLET TRAILBLAZER LT EQUIPPED WITH CONTINENTAL CONTITRAC TR TIRES (SIZE:P245/65R17) THAT WERE USED ON THE FRONT AND REAR. THE CONTACT STATED THAT THE SIDE WALLS HAD BECOME SEPARATED FROM THE TIRE. PRIOR TO THE FAILURE, THE CONTACT NOTICED THAT AN ABNORMAL WOBBLE NOISE WAS BEING EMITTED FROM THE TIRES WHEN DRIVING. THE MANUFACTURER WAS NOT NOTIFIED OF THE FAILURE. THE FAILURE MILEAGE OF THE TIRE WAS 51,000 AND THE FAILURE MILEAGE ON THE VEHICLE AT THE TIME OF THE FAILURE. . ....UPDATED 05/23/12 *BF CONSUMER STATED TWO TIRES ON VEHICLE FAILED WITHIN 1500 MILES OF EACH OTHER (FIRST ONE FAILED ON DRIVERS SIDE AND SECOND ON PASSENGER SIDE REAR). CONSUMER CONTACTED CONTINENTAL TIRES ABOUT HAVING TIRES REPLACED BUT BECAUSE WARRANTY HAD EXPIRED CONTINENTAL TIRES WOULD NOT REPLACE THEM . CONSUMER CALLED NHTSA AND FILED A COMPLAINT. UPDATED 6/6/12 *SD

NHTSA ODI #10456901

98,000 miles · Apr 27, 2012
Electrical System

TL* THE CONTACT OWNS A 2004 CHEVROLET TRAILBLAZER. WHILE TRAVELING AT VARIOUS SPEEDS, THE CONTACT NOTICED THAT ALL OF THE GAUGES ON THE INSTRUMENT PANEL FAILED. THE VEHICLE WAS TAKEN TO THE DEALER WHERE THE CONTACT WAS INFORMED THAT THE INSTRUMENT PANEL NEEDED TO BE REPLACED. THE VEHICLE WAS NOT REPAIRED. THE CURRENT MILEAGE WAS…

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TL* THE CONTACT OWNS A 2004 CHEVROLET TRAILBLAZER. WHILE TRAVELING AT VARIOUS SPEEDS, THE CONTACT NOTICED THAT ALL OF THE GAUGES ON THE INSTRUMENT PANEL FAILED. THE VEHICLE WAS TAKEN TO THE DEALER WHERE THE CONTACT WAS INFORMED THAT THE INSTRUMENT PANEL NEEDED TO BE REPLACED. THE VEHICLE WAS NOT REPAIRED. THE CURRENT MILEAGE WAS 101,000 AND THE FAILURE MILEAGE WAS 98,000.

NHTSA ODI #10456694

50,000 miles · Apr 6, 2012
Electrical System

TL* THE CONTACT OWNS A 2004 CHEVROLET TRAILBLAZER. THE CONTACT STATED THAT THE DIGITAL INSTRUMENT PANEL FAILED. THE CONTACT WAS UNABLE TO READ THE SPEED TRAVELED, MILEAGE OR FUEL LEVELS. THE MANUFACTURER WAS CONTACTED AND STATED THAT THE INSTRUMENT PANEL WAS NOT UNDER WARRANTY. THE VEHICLE WAS NOT REPAIRED. THE VIN WAS NOT AVAIL…

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TL* THE CONTACT OWNS A 2004 CHEVROLET TRAILBLAZER. THE CONTACT STATED THAT THE DIGITAL INSTRUMENT PANEL FAILED. THE CONTACT WAS UNABLE TO READ THE SPEED TRAVELED, MILEAGE OR FUEL LEVELS. THE MANUFACTURER WAS CONTACTED AND STATED THAT THE INSTRUMENT PANEL WAS NOT UNDER WARRANTY. THE VEHICLE WAS NOT REPAIRED. THE VIN WAS NOT AVAILABLE. THE FAILURE MILEAGE WAS 50,000 AND THE CURRENT MILEAGE WAS 73,000.

NHTSA ODI #10454380

60,000 miles · Mar 30, 2012
Electrical SystemFuel System, Other

FUEL GAUGE HAS BEEN FLUCTUATING WILDLY FOR A COUPLE OF MONTHS, GENERALLY READING EMPTY (EVEN AFTER FILL UP) BUT OCCASIONALLY FULL (WHEN A FILL UP IS NEEDED). DEALER SAID FUEL GAUGE SENSOR WAS BAD & THAT IT WOULD BE APPROX $900 TO FIX. LOOKING INTO THE PROBLEM ONLINE I SEE THERE ARE THOUSANDS OF PEOPLE WITH THE SAME PROBLEM. …

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FUEL GAUGE HAS BEEN FLUCTUATING WILDLY FOR A COUPLE OF MONTHS, GENERALLY READING EMPTY (EVEN AFTER FILL UP) BUT OCCASIONALLY FULL (WHEN A FILL UP IS NEEDED). DEALER SAID FUEL GAUGE SENSOR WAS BAD & THAT IT WOULD BE APPROX $900 TO FIX. LOOKING INTO THE PROBLEM ONLINE I SEE THERE ARE THOUSANDS OF PEOPLE WITH THE SAME PROBLEM. *JS

NHTSA ODI #10453574

98,000 miles · Mar 22, 2012
Electrical System

THE STEPPER MOTORS IN THE INSTRUMENT CLUSTER HAVE FAILED. THIS IS AN EXTREMELY COMMON PROBLEM AND PEOPLE ARE NOW MAKING A LIVING OFF OF CHARGING FOR THE REPAIRS BECAUSE GM IS REFUSING TO ISSUE A RECALL. *TR

NHTSA ODI #10452689

80,000 miles · Mar 21, 2012
Fuel System, Gasoline

TL* THE CONTACT OWNS A 2004 CHEVROLET TRAIL BLAZER. THE CONTACT STATED THAT AFTER REFUELING, THE SMELL OF GASOLINE FUEL WAS EMITTED INSIDE OF THE VEHICLE. THE CHECK ENGINE WARNING LIGHT WAS ALSO ILLUMINATED DURING THE FAILURE . THE VEHICLE WAS TAKEN TO A PRIVATE MECHANIC WHERE THE MECHANIC CONFIRMED THAT THE FUEL TANK NEEDED TO…

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TL* THE CONTACT OWNS A 2004 CHEVROLET TRAIL BLAZER. THE CONTACT STATED THAT AFTER REFUELING, THE SMELL OF GASOLINE FUEL WAS EMITTED INSIDE OF THE VEHICLE. THE CHECK ENGINE WARNING LIGHT WAS ALSO ILLUMINATED DURING THE FAILURE . THE VEHICLE WAS TAKEN TO A PRIVATE MECHANIC WHERE THE MECHANIC CONFIRMED THAT THE FUEL TANK NEEDED TO BE REPLACED DUE TO A LEAK. THE MANUFACTURER WAS NOT CONTACTED. THE VEHICLE WAS NOT REPAIRED. THE FAILURE MILEAGE WAS 80,000 AND THE CURRENT MILEAGE WAS 99,000.

NHTSA ODI #10452544

Official recalls

2

05V198000 · Exterior Lighting:turn Signal

May 5, 2005

ON CERTAIN TRUCKS AND SPORT UTILITY VEHICLES, THE DRIVER WISHING TO SIGNAL A TURN BY MOVING THE DIRECTIONAL SIGNAL LEVER, (UP OR DOWN) MAY CAUSE THE FRONT MARKER/TURN LIGHTS AND REAR TURN LIGHTS TO FLASH IN A MANNER SIMILAR TO HAZARD WARNING, RATHER THAN FLASHING ON THE DESIRED SIDE ONLY.

Consequence & remedy

Consequence: THE DRIVER MAY NOT BE ABLE TO CLEARLY SIGNAL THEIR INTENTIONS TO TURN, CHANGE TRAVEL LANES, OR POTENTIALLY WARN OTHERS OF AN IMPAIRED VEHICLE OPERATING CONDITION INCREASING THE RISK OF A CRASH.

Remedy: DEALERS WILL REPLACE THE SUSPECT FLASHER MODULES WITH A NEW FLASHER MODULE DESIGNED WITH SEALED RELAYS AND MORE DURABLE CONTACT MATERIAL INSIDE OF THE RELAYS FREE OF CHARGE. THE RECALL BEGAN ON AUGUST 4, 2005. ISUZU BEGAN MAILING OWNER LETTERS ON AUGUST 4, 2005. OWNERS MAY CONTACT CHEVROLET AT 1-800-630-2438, GMC AT 1-866-996-9463, ISUZU AT 1-800-255-6727, BUICK AT 1-866-608-8080, AND OLDSMOBILE AT 1-800-630-6537.

04V527000 · Exterior Lighting:brake Lights

Nov 1, 2004

ON CERTAIN SPORT UTILITY VEHICLES, VIBRATION AND HEAT MAY CAUSE THE TAIL LAMP/STOP LAMP BULB TO LOOSEN IN ITS SOCKET. IF THIS OCCURS, THE BULB MAY FLICKER AND EVENTUALLY BECOME INOPERATIVE.

Consequence & remedy

Consequence: AN INOPERATIVE BRAKE LAMP WILL NOT CONVEY THE DRIVER'S INTENTION OF STOPPING TO DRIVERS IN FOLLOWING VEHICLES, AND AN INOPERATIVE REAR TURN SIGNAL LAMP WILL NOT CONVEY THE DRIVER'S INTENTION TO TURN TO DRIVERS IN FOLLOWING VEHICLES. BOTH OF THESE FAILURES CAN INCREASE THE RISK OF A CRASH.

Remedy: DEALERS WILL INSPECT THE TAIL LAMP/STOP LAMP ASSEMBLIES, AND IF NECESSARY, REPLACE THEM. THE RECALL BEGAN ON NOVEMBER 22, 2004. OWNERS SHOULD CONTACT CHEVROLET AT 1-800-630-2438, OLDSMOBILE AT 1-800-630-6537, BUICK AT 1-866-608-8080, OR GMC AT 1-866-996-9463.

Model-level recall history does not show whether a particular VIN is affected or has received a repair. Check a VIN with NHTSA ↗

NHTSA investigations

4

RQ17002 · Loss Of Headlights

Opened Apr 24, 2017 · Closed Mar 29, 2021

Status: closed (inferred from source dates) · Exterior Lighting:headlights

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.

EA07009 · Fuel Pump Module Leaks Gasoline

Opened Jul 10, 2007 · Closed Aug 28, 2008

Status: closed (inferred from source dates) · Fuel System, Gasoline:delivery:fuel Pump

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.

EA04021 · Brake Lamp Failure

Opened Aug 3, 2004 · Closed Nov 4, 2004

Status: closed (inferred from source dates) · Exterior Lighting:brake Lights

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.

PE04032 · Brake Lamp Failure

Opened Apr 6, 2004 · Closed Aug 3, 2004

Status: closed (inferred from source dates) · Exterior Lighting:brake Lights

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.