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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.

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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

Electrical System complaints

627 reports
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55,000 miles · Mar 4, 2009
Electrical System

AT APPROXIMATELY 55,000 MILES I NOTICED MY SPEEDOMETER CLICKING AT 5MPH INTERVALS. THE PROBLEM PERSISTED WHEN I WAS PULLED OVER GOING 10MPH OVER THE SPEED LIMIT WHEN IT APPEARED I WAS GOING THE POSTED SPEED. THE PROBLEM GOT WORSE WHEN MY SPEEDOMETER STARTED STICKING, AND FINALLY ROTATING ALL THE WAY PASSED TOP SPEED BACK TO ZE…

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AT APPROXIMATELY 55,000 MILES I NOTICED MY SPEEDOMETER CLICKING AT 5MPH INTERVALS. THE PROBLEM PERSISTED WHEN I WAS PULLED OVER GOING 10MPH OVER THE SPEED LIMIT WHEN IT APPEARED I WAS GOING THE POSTED SPEED. THE PROBLEM GOT WORSE WHEN MY SPEEDOMETER STARTED STICKING, AND FINALLY ROTATING ALL THE WAY PASSED TOP SPEED BACK TO ZERO. THIS MALFUNCTION SPREAD TO MY TACHOMETER WHERE IT SHOWS I AM TRAVELING AT MORE THAN MORE THAN 11,000 RPMS AT CRUISING SPEEDS ON THE HIGHWAY. THEN MY GAS GAUGE BEGAN TO MALFUNCTION. THE READING PUT ME AT NEARLY 200% CAPACITY, MAKING IT IMPOSSIBLE TO KNOW HOW MUCH FUEL I HAD. SO I BEGAN USING MY ODOMETER TO GAUGE MY FUEL UNTIL I NOTICED MY ODOMETER READING 2-4 TENTHS OF A MILE EVERY 1/10. I HAVE ALREADY RECEIVED 2 SPEEDING TICKETS DUE TO THIS PROBLEM. IT IS ONLY A MATTER OF TIME BEFORE I AM STRANDED OUT OF GAS. I SEE THERE ARE PLENTY OF COMPLAINTS FROM CONSUMERS WITH THE SAME PROBLEM. I HAVE NO IDEA OF ANY RELATED DEATHS OR INJURIES DUE TO THIS PROBLEM, BUT THIS IS OBVIOUSLY A GM DEFECT NOT RELATED TO REGULAR SCHEDULED MAINTENANCE THAT SHOULD BE TAKEN CARE OF BY THE MANUFACTURER. NOT ONLY CAN THIS ISSUE ONLY BE REPAIRED BY A DEALERSHIP AT OUTRAGEOUS FEES (ESTIMATED $550), BUT THEIR DEFECTIVE PART IS NOW GIVING A FAULTY ODOMETER READING WHICH AGAINST MISSOURI STATE LAW. *TR

NHTSA ODI #10260743

Mileage unknown · Mar 3, 2009
Electrical System

FIRST WHEN I BOUGHT MY CERTIFIED PRE OWNED TRAIL BLAZER THE TACHOMETER WENT OUT AND POINTED STRAIGHT DOWN THEN A COUPLE MONTHS LATER MY WHOLE INSTRUMENT CLUSTER WENT COMPLETELY HAY WIRE. THE SPEEDOMETER, TACH, OIL PRESSURE, GAS GAUGE, EVERYTHING NEEDED TO EFFECTIVELY DRIVE HAS GONE WRONG. I CANNOT TELL IF I AM SPEEDING, IF I AM …

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FIRST WHEN I BOUGHT MY CERTIFIED PRE OWNED TRAIL BLAZER THE TACHOMETER WENT OUT AND POINTED STRAIGHT DOWN THEN A COUPLE MONTHS LATER MY WHOLE INSTRUMENT CLUSTER WENT COMPLETELY HAY WIRE. THE SPEEDOMETER, TACH, OIL PRESSURE, GAS GAUGE, EVERYTHING NEEDED TO EFFECTIVELY DRIVE HAS GONE WRONG. I CANNOT TELL IF I AM SPEEDING, IF I AM OUT OF FUEL , IF MY ENGINE WILL OVER HEAT AND THIS IS ALL VERY DANGEROUS ON THE HIGHWAY, I WORRY CONSTANTLY. I HAVE TAKEN IT IN TO BE FIXED BUT CANNOT AFFORD IT BECAUSE I AM PAYING FOR MY COLLEGE. THIS IS A VERY COMMON PROBLEM WITH THESE VEHICLES AND GMC/CHEVY SHOULD DO SOMETHING TO FIX THIS SAFETY HAZARD. *TR

NHTSA ODI #10260595

75,000 miles · Mar 2, 2009
Electrical System

IT STARTED OUT WITH THE TAC NOT ALWAYS WORKING. NOW THE SPEEDOMETER DOES NOT WORK. WHEN I AM ON THE INTERSTATE IT USUALLY READS LESS THAN ACTUAL AND WHEN I AM IN TOWN DRIVING IT OFTEN INDICATES A HIGHER SPEED. I BELIEVE THERE ARE NOW PROBLEMS WITH THE GAS GAUGE. *TR

NHTSA ODI #10260454

Mileage unknown · Mar 2, 2009
Electrical System

I HAVE A 2004 CHEVY TRAILBLAZER LS V6 2WD. MY SPEEDOMETER WENT OUT ON ME WHILE I WAS DRIVING. AT ONE POINT IT WAS STUCK AT 120 MPH. I WAS TOLD BY GM THAT THEY HAVE THE SAME PROBLEM WITH OTHER MODEL AND MADE A RECALL ON THEM. WHEN I ASKED IF THERE WAS A RECALL FOR THE 2004 MODEL THEY TOLD ME THAT THERE WAS NOT BECAUSE NOT ENOUGH …

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I HAVE A 2004 CHEVY TRAILBLAZER LS V6 2WD. MY SPEEDOMETER WENT OUT ON ME WHILE I WAS DRIVING. AT ONE POINT IT WAS STUCK AT 120 MPH. I WAS TOLD BY GM THAT THEY HAVE THE SAME PROBLEM WITH OTHER MODEL AND MADE A RECALL ON THEM. WHEN I ASKED IF THERE WAS A RECALL FOR THE 2004 MODEL THEY TOLD ME THAT THERE WAS NOT BECAUSE NOT ENOUGH PEOPLE COMPLAINING. TO ME IT SOUNDS LIKE THEY KNOW IT'S A PROBLEM BUT WILL NOT DO ANYTHING ABOUT IT. *TR

NHTSA ODI #10260410

37,001 miles · Mar 2, 2009
Electrical System

SPEEDOMETER OF 2004 CHEVY TRAILBLAZER IS BROKEN. IT WORKS SOMETIMES, BUT RECENTLY I AM CLUELESS ON WHAT SPEED I'M GOING . I MIGHT GO 55 MPH AND IT READS 120 MPH OR I'LL GO 40MPH AND IT'LL READ 10MPH. ??? *TR

NHTSA ODI #10260395

72,000 miles · Mar 1, 2009
Electrical System

2004 CHEVROLET TRAILBLAZER SPEEDOMETER STUCK AT 80 MPH. *TR

NHTSA ODI #10260364

60,000 miles · Feb 20, 2009
Electrical System

ARE YOU GUYS (GALS) READING THE COMPLAINTS CENTERED AROUND 2004 TRAILBLAZER AND THE PROBLEMS WITH ELECTRICAL SYSTEMS "INSTRUMENT CLUSTER" MALFUNCTIONS? I HAVE!! THERE ARE ONE AFTER ANOTHER COMPLAINING ABOUT EITHER MIS-READINGS OR NO READING OF INSTRUMENT GAUGES! MY 2004 TRAILBLAZER HAS 70M MILES AND THE RPM READING IS MIS-READIN…

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ARE YOU GUYS (GALS) READING THE COMPLAINTS CENTERED AROUND 2004 TRAILBLAZER AND THE PROBLEMS WITH ELECTRICAL SYSTEMS "INSTRUMENT CLUSTER" MALFUNCTIONS? I HAVE!! THERE ARE ONE AFTER ANOTHER COMPLAINING ABOUT EITHER MIS-READINGS OR NO READING OF INSTRUMENT GAUGES! MY 2004 TRAILBLAZER HAS 70M MILES AND THE RPM READING IS MIS-READING AS WELL. GET GM TO RECALL THIS VEHICLE JUST AS THEY HAVE BEEN FORCED TO WITH OTHER PASSENGER & TRUCK MODELS. SPEEDOMETER AND GAUGE MIS-READINGS ARE A VERY SERIOUS HAZARDS TO DRIVING AND SAFETY TO THE PUBLIC. WHAT ELSE DO YOU NEED TO TAKE GM ON! *TR

NHTSA ODI #10259454

66,000 miles · Feb 19, 2009
Electrical SystemFuel System, Gasoline

TL*THE CONTACT OWNS A 2004 CHEVROLET TRAILBLAZER. THE CONTACT SMELLED A STRONG ODOR OF GASOLINE COMING FROM THE VEHICLE. IN ADDITION, THE ENGINE WARNING INDICATOR ILLUMINATED SPORADICALLY ON THE INSTRUMENT CONTROL PANEL. SHE TOOK HER VEHICLE TO THE DEALER AND THEY STATED THAT FUEL VAPORS WERE LEAKING AND COLLECTING ON TOP OF …

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TL*THE CONTACT OWNS A 2004 CHEVROLET TRAILBLAZER. THE CONTACT SMELLED A STRONG ODOR OF GASOLINE COMING FROM THE VEHICLE. IN ADDITION, THE ENGINE WARNING INDICATOR ILLUMINATED SPORADICALLY ON THE INSTRUMENT CONTROL PANEL. SHE TOOK HER VEHICLE TO THE DEALER AND THEY STATED THAT FUEL VAPORS WERE LEAKING AND COLLECTING ON TOP OF THE MODULE. THE FAILURE CAUSED FUEL TO SPILL ONTO THE GROUND. THE CONTACT WOULD HAVE TO PAY $1,300 TO HAVE THE VEHICLE REPAIRED BECAUSE IT WAS NOT REGISTERED IN A SALT BELT STATE. SECONDLY, SHE NOTICED THAT THE GAUGES ON THE INSTRUMENT PANEL WERE INOPERATIVE AND DISPLAYED INACCURATE INFORMATION. THE DEALER STATED THAT THE VIN WAS NOT INCLUDED IN THE MANUFACTURER'S RECALL FOR THE INSTRUMENT CONTROL PANEL; THEREFORE, SHE WOULD HAVE TO PAY $550 TO REPAIR THE COMPONENT. CURRENTLY, NO REPAIRS HAVE BEEN MADE. THE FAILURE MILEAGE WAS 66,000 AND CURRENT MILEAGE IS 73,000. UPDATED 3/11/09 *CN UPDATED 03/13/09. *JB

NHTSA ODI #10259328

43,000 miles · Feb 18, 2009
Electrical System

I HAVE AN 04 TRAILBLAZER WITH ONLY 43000 MILES THAT HAS DEVELOPED AN OBVIOUS RECURRING PROBLEM WITH THE GAUGE CLUSTER FAILING AND READING INACCURATELY. I REALIZE THAT INVESTIGATIONS HAVE SHOWED NO DEATHS OR INJURIES DUE TO THIS FAILURE HOWEVER DOES IT NOT PRODUCE AND INCREASED SAFETY RISK AND SHOULD BE RECALLED? WHAT IS BEING D…

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I HAVE AN 04 TRAILBLAZER WITH ONLY 43000 MILES THAT HAS DEVELOPED AN OBVIOUS RECURRING PROBLEM WITH THE GAUGE CLUSTER FAILING AND READING INACCURATELY. I REALIZE THAT INVESTIGATIONS HAVE SHOWED NO DEATHS OR INJURIES DUE TO THIS FAILURE HOWEVER DOES IT NOT PRODUCE AND INCREASED SAFETY RISK AND SHOULD BE RECALLED? WHAT IS BEING DONE TO CORRECT THIS BESIDES OWNERS HAVING TO SHELL OUT OVER $500 FOR THE REPAIR? *TR

NHTSA ODI #10259279

65,000 miles · Feb 17, 2009
Electrical System

THE ENGINE TEMPERATURE AND BATTERY CHARGE METER ARE INOPERATIVE, THE NEEDLES POINT DOWN (OFF THE GAUGE). THE SPEEDOMETER AND TACH GAUGES ALSO WORK INTERMITTENTLY. THE DEALER OFFERED TO REPLACE THE ENTIRE INSTRUMENT CLUSTER FOR APPROX $700, BUT THIS PART IS NOT UNDER ANY KIND OF ORIGINAL OR EXTENDED WARRANTY. THIS SAME PART WA…

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THE ENGINE TEMPERATURE AND BATTERY CHARGE METER ARE INOPERATIVE, THE NEEDLES POINT DOWN (OFF THE GAUGE). THE SPEEDOMETER AND TACH GAUGES ALSO WORK INTERMITTENTLY. THE DEALER OFFERED TO REPLACE THE ENTIRE INSTRUMENT CLUSTER FOR APPROX $700, BUT THIS PART IS NOT UNDER ANY KIND OF ORIGINAL OR EXTENDED WARRANTY. THIS SAME PART WAS RECALLED ON SEVERAL OTHER GM MODELS, BUT NOT INCLUDING THE TRAILBLAZER. NOT HAVING A TEMPERATURE GAUGE AND SPEEDOMETER HAS POTENTIALLY SERIOUSLY DANGEROUS CONSEQUENCES, GM NEEDS TO RECALL AND REPLACE THIS PART IMMEDIATELY. *TR

NHTSA ODI #10259132

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.