IllustrationSPEEDOMETER GAUGE, FUEL GAUGE, TEMP. GUAGE NOT WORKING. ONLY THE RPM AND TEMP GAUGE WORKING AT THIS TIME.
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 →How this year compares
Owner complaints by model year
Compare all Trailblazer years →Counts vary with age, sales and reporting. They are not failure rates.
What owners reported most
All reported categories
Tap a category to read its complaints. One report may name several components.
When problems were reported
Mileage at the reported incident
880–25K
16325–50K
27450–75K
17675–100K
137100–150K
61150K+
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 reportsTHE SPEEDOMETER ON MY 2004 TRAILBLAZER OPERATES VERY ERRATICALLY. AT TIMES IT DOES NOT WORK AT ALL AT TIMES IT REGISTERS WAY SLOW OR WAY FAST. THIS TO ME IS A MAJOR SAFETY ISSUE. IF DRIVING ON SNOWY ROADS YOU CAN NOT TELL HOW FAST YOUR WHEELS ARE SPINNING AND THIS COULD CAUSE LOSS OF CONTROL OF THE VEHICLE. OR ANOTHER SCENARIO, …
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THE SPEEDOMETER ON MY 2004 TRAILBLAZER OPERATES VERY ERRATICALLY. AT TIMES IT DOES NOT WORK AT ALL AT TIMES IT REGISTERS WAY SLOW OR WAY FAST. THIS TO ME IS A MAJOR SAFETY ISSUE. IF DRIVING ON SNOWY ROADS YOU CAN NOT TELL HOW FAST YOUR WHEELS ARE SPINNING AND THIS COULD CAUSE LOSS OF CONTROL OF THE VEHICLE. OR ANOTHER SCENARIO, TRAVELING ON THE INTERSTATE AND THE MILES PER HOUR IS REGISTERING BETWEEN 5 AND 10 MPH LESS THAT YOU ARE ACTUALLY TRAVELING. THIS COULD POSE A REAR END COLLISION PROBLEM AS THOSE TRAVELING BEHIND YOU MAY NOT NOTICE THAT YOUR SPEED IS SLOWER. A PROPERLY FUNCTIONING SPEEDOMETER IS A VITAL PART OF BEING ABLE TO DRIVE THE VEHICLE IN A SAFE MANNER, NOT ONLY FOR YOUR SAFETY BUT FOR THOSE AROUND YOU. IN SEARCHING THE INTERNET THIS SEEMS TO BE MORE OF A "COMMON" PROBLEM THAN WHAT ONE MIGHT REALIZE. GENERAL MOTORS SHOULD BE HELD ACCOUNTABLE FOR THIS PROBLEM, AS A PROPERLY FUNCTIONING SPEEDOMETER IS AN IMPORTANT SAFETY FEATURE. THE SAME AS BRAKES FAILURE, THROTTLE STICKING, FIRE HAZARD OR ANY OTHER MYRIAD OF ITEMS ON A VEHICLE ARE RELATED TO THE PROPER AND SAFE OPERATION BEYOND THE OPERATORS CONTROL. PLEASE LOOK INTO THIS. THANK YOU *TR
TL* THE CONTACT OWNS A 2004 CHEVROLET TRAILBLAZER. WHILE AT A STOP LIGHT, THE CONTACT NOTICED THE SPEEDOMETER WAS PROVIDING A SPEED READING OF 60 MPH. THE READING OF THE OTHER GAUGES ON THE INSTRUMENT PANEL ALSO FLUCTUATED ERRATICALLY. THE VEHICLE WAS NOT TAKEN TO THE DEALER FOR DIAGNOSTIC TESTING OR REPAIRS. THE APPROXIMATE FA…
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TL* THE CONTACT OWNS A 2004 CHEVROLET TRAILBLAZER. WHILE AT A STOP LIGHT, THE CONTACT NOTICED THE SPEEDOMETER WAS PROVIDING A SPEED READING OF 60 MPH. THE READING OF THE OTHER GAUGES ON THE INSTRUMENT PANEL ALSO FLUCTUATED ERRATICALLY. THE VEHICLE WAS NOT TAKEN TO THE DEALER FOR DIAGNOSTIC TESTING OR REPAIRS. THE APPROXIMATE FAILURE MILEAGE WAS 60,000. UPDATED 02/14/12*LJ UPDATED 02/17/12
TL* THE CONTACT OWNS A 2004 CHEVROLET TRAILBLAZER. THE CONTACT NOTICED THAT THE INSTRUMENT PANEL READINGS BEGAN TO FLUCTUATE ERRATICALLY. THE FAILURE RECURRED INTERMITTENTLY. THE VEHICLE WAS NOT TAKEN TO THE DEALER FOR DIAGNOSTICS OR REPAIRS. THE VIN WAS NOT AVAILABLE. THE APPROXIMATE FAILURE MILEAGE WAS 62,000.
TL* THE CONTACT OWNS A 2004 CHEVROLET TRAILBLAZER. THE CONTACT STATED THAT AFTER REFUELING, FUEL WOULD SPILL OUT FROM THE FILLER NECK. THE VEHICLE WAS TAKEN TO A DEALER WHERE THEY ADVISED HER THAT THERE WAS A HOLE IN THE FUEL TANK AND THE FILLER WAS FRACTURED. THE ENTIRE FUEL TANK WOULD NEED TO BE REPLACED. THE VEHICLE FUEL TAN…
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TL* THE CONTACT OWNS A 2004 CHEVROLET TRAILBLAZER. THE CONTACT STATED THAT AFTER REFUELING, FUEL WOULD SPILL OUT FROM THE FILLER NECK. THE VEHICLE WAS TAKEN TO A DEALER WHERE THEY ADVISED HER THAT THERE WAS A HOLE IN THE FUEL TANK AND THE FILLER WAS FRACTURED. THE ENTIRE FUEL TANK WOULD NEED TO BE REPLACED. THE VEHICLE FUEL TANK WAS REPLACED. THE MANUFACTURER WAS NOT MADE AWARE OF THE FAILURE. THE FAILURE MILEAGE WAS APPROXIMATELY 110,000.
TL* THE CONTACT OWNS A 2004 CHEVROLET TRAILBLAZER. THE CONTACT STATED THAT ALL OF THE INSTRUMENT PANEL GAUGES FAILED. THE CONTACT SPOKE WITH THE MANUFACTURER AND WAS TOLD THERE WERE NO RECALLS FOR THE FAILURE AND THAT ENTIRE INSTRUMENT PANEL WOULD NEED TO BE REPLACED. THE VEHICLE WAS NOT REPAIRED. THE FAILURE MILEAGE WAS 70,000…
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TL* THE CONTACT OWNS A 2004 CHEVROLET TRAILBLAZER. THE CONTACT STATED THAT ALL OF THE INSTRUMENT PANEL GAUGES FAILED. THE CONTACT SPOKE WITH THE MANUFACTURER AND WAS TOLD THERE WERE NO RECALLS FOR THE FAILURE AND THAT ENTIRE INSTRUMENT PANEL WOULD NEED TO BE REPLACED. THE VEHICLE WAS NOT REPAIRED. THE FAILURE MILEAGE WAS 70,000 AND THE CURRENT MILEAGE WAS 104,000.
TRANS LEAK FROM TRANS COOLER LINES. *TR
TL* THE CONTACT OWNS A 2004 CHEVROLET TRAILBLAZER. THE CONTACT STATED THAT THERE WAS A FRACTURE IN THE FUEL NECK LINE, CAUSING A FUEL LEAK. THE CONTACT TOOK THE VEHICLE TO THE DEALER WHERE THE DEALER STATED TO THE CONTACT THAT THE FUEL TANK NEEDED TO BE REPLACED. THE VEHICLE WAS NOT REPAIRED. THE FAILURE MILEAGE WAS 103,000. …
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TL* THE CONTACT OWNS A 2004 CHEVROLET TRAILBLAZER. THE CONTACT STATED THAT THERE WAS A FRACTURE IN THE FUEL NECK LINE, CAUSING A FUEL LEAK. THE CONTACT TOOK THE VEHICLE TO THE DEALER WHERE THE DEALER STATED TO THE CONTACT THAT THE FUEL TANK NEEDED TO BE REPLACED. THE VEHICLE WAS NOT REPAIRED. THE FAILURE MILEAGE WAS 103,000.
MY 2004 CHEVY TRAILBLAZER INSTRUMENT GAUGES STARTED GOING HAYWIRE. EVERYTHING THAT I HAVE READ SAYS THE WHOLE PANEL NEEDS REPLACED. THE OIL, BATTERY, TEMP AND GAS CLUSTERS STOPPED WORKING THEN ALL OF A SUDDEN WHILE DRIVING DOWN THE ROAD START WORKING AGAIN. THEN THE SPEEDOMETER AND TACH STOPPED AND STARTED AND NOW NOTHING IS COM…
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MY 2004 CHEVY TRAILBLAZER INSTRUMENT GAUGES STARTED GOING HAYWIRE. EVERYTHING THAT I HAVE READ SAYS THE WHOLE PANEL NEEDS REPLACED. THE OIL, BATTERY, TEMP AND GAS CLUSTERS STOPPED WORKING THEN ALL OF A SUDDEN WHILE DRIVING DOWN THE ROAD START WORKING AGAIN. THEN THE SPEEDOMETER AND TACH STOPPED AND STARTED AND NOW NOTHING IS COMING ON. I HAVE NO IDEA HOW MUCH FUEL THAT I HAVE AND ALL OF THE WARNING LIGHTS ARE ALL LIT UP. WAITING FOR THE WHOLE THING TO BLOW. I CURRENTLY HAVE IT AT A GM DEALER AND THEY SAID THAT IT WILL COST ME 500 BUCKS TO REPLACE THE PANEL. I TOLD THEM TO GO AHEAD BECAUSE I DON'T FEEL SAFE DRIVING LIKE THAT. I HAVE TO HAVE THIS VEHICLE TO WORK AND I WANT GM TO PAY FOR THIS TO BE FIXED. MAJOR SAFETY CONCERN FOR ME! *TR
WHEN I FIRST PURCHASED THIS VEHICLE I THOUGHT I HAD A GREAT SUV. LITTLE DID I KNOW THAT WITHIN THE FIRST MONTH OF OWNING IT DID I MAKE A HUGE MISTAKE. I AM A SINGLE MOTHER OF 2 KIDS. I CHECKED OUT THE CRASH RATINGS AND THEY WERE GREAT!! I LIKED EVERYTHING ABOUT MY TB. LOOKING BACK, AFTER THE 4TH PROBLEM WITHIN THAT FIRST MONTH. …
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WHEN I FIRST PURCHASED THIS VEHICLE I THOUGHT I HAD A GREAT SUV. LITTLE DID I KNOW THAT WITHIN THE FIRST MONTH OF OWNING IT DID I MAKE A HUGE MISTAKE. I AM A SINGLE MOTHER OF 2 KIDS. I CHECKED OUT THE CRASH RATINGS AND THEY WERE GREAT!! I LIKED EVERYTHING ABOUT MY TB. LOOKING BACK, AFTER THE 4TH PROBLEM WITHIN THAT FIRST MONTH. I SHOULD HAVE RAN AWAY SCREAMING FROM IT, AS I DO NOW DAILY. THE LIGHTS FLICKER WHEN YOU DRIVE AT NIGHT. THE HEADLIGHTS CONSTANTLY GO OUT. THE CHECK GAUGES LIGHT IS CONSTANTLY COMING ON. THE OIL PRESSURE GAUGE DROPS FOR NO APPARENT REASON. THE TACH GOES CRAZY. THE "BELL" FOR THE LIGHTS (WHEN YOU HAVE THE KEYS OUT AND THE LIGHTS ARE STILL ON, OR WHEN YOU HAVE THE KEYS IN AND THE DRIVERS DOOR OPEN) WORKS WHEN IT WANTS TO. THE BATTERY GAUGE WORKS WHEN IT FEELS LIKE IT. THE GAS GAUGE HASN'T HAD A PROBLEM LATELY. I AM WONDERING...DOESN'T ALL OF THAT CONSTITUTE AS A SAFETY PROBLEM?? I HAVE HAD THE LIGHTS LOOKED AT AND AM TOLD THERE ISN'T ANYTHING THAT CAN BE DONE..REALLY?? I AM GOING TO HAVE TO HAVE THE GAUGES LOOKED AT NOW AND FROM WHAT I SEE IT WILL COST ABOUT $600-$800. WHERE OTHER CHEVY VEHICLES HAVE HAD THIS COVERED UNDER A RECALL. THERE ARE MANY OTHER PROBLEMS I'VE HAD, THE O2 SENSOR, TEMP GAUGE, OTHER LIGHTING ISSUES THAT I HAVE TAKEN CARE OF BUT THIS IS GETTING TO BE A BIT MUCH. I SEE MANY OTHERS HAVE HAD THIS PROBLEM. IT CAN'T BE FROM NORMAL WEAR ON THE VEHICLE. PLEASE DO SOMETHING ABOUT THIS BEFORE SOMEONE'S FAMILY REALLY GETS HURT, IF THEY HAVEN'T ALREADY. *TR
Official recalls
205V198000 · 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
4RQ17002 · 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.