NHTSA owner reports · September 18, 2026 snapshot.
Engine And Engine Cooling complaints
39 reportsClear category filter100 miles · Feb 12, 2010
Engine And Engine Cooling
TL*THE CONTACT OWNS A 2004 CHEVROLET TRAILBLAZER. THE CONTACT STARTED THE IGNITION AND SUDDENLY, THERE WAS A LOUD NOISE OUTSIDE OF THE VEHICLE. THE VEHICLE WAS TAKEN TO AN AUTHORIZED DEALER FOR DIAGNOSTIC TESTING. THE FAILURE WAS CONTRIBUTED TO THE SECONDARY AIR INJECTION SYSTEM. THE CONTACT REPAIRED THE VEHICLE. THE COMPONENT …
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TL*THE CONTACT OWNS A 2004 CHEVROLET TRAILBLAZER. THE CONTACT STARTED THE IGNITION AND SUDDENLY, THERE WAS A LOUD NOISE OUTSIDE OF THE VEHICLE. THE VEHICLE WAS TAKEN TO AN AUTHORIZED DEALER FOR DIAGNOSTIC TESTING. THE FAILURE WAS CONTRIBUTED TO THE SECONDARY AIR INJECTION SYSTEM. THE CONTACT REPAIRED THE VEHICLE. THE COMPONENT FAILED THREE MONTHS AFTER THE VEHICLE WAS REPAIRED. THE VEHICLE HAS NOT BEEN REPAIRED AT THIS TIME. THE VIN WAS UNAVAILABLE. THE FAILURE MILEAGE WAS 100.
NHTSA ODI #10308899
78,000 miles · Aug 20, 2009
Engine And Engine Cooling
I WAS TRAVELING ON THE HIGHWAY WHEN I HERD A RATTLING SOUND COMING FROM THE ENGINE, GOT OFF THE HIGHWAY AND PULL INTO A STATION. CALL THE TOW COMPANY TO TOW IT TO MY MECHANIC HE SAID THE WATER PUMP BEARINGS BROKE AND THE FAN STOP TURNING SINCE BOTH ARE CONNECTED TOGETHER, HE SAID THE ENGINE MIGHT BE DAMAGE POSSIBLE DUE TO OVERHE…
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I WAS TRAVELING ON THE HIGHWAY WHEN I HERD A RATTLING SOUND COMING FROM THE ENGINE, GOT OFF THE HIGHWAY AND PULL INTO A STATION. CALL THE TOW COMPANY TO TOW IT TO MY MECHANIC HE SAID THE WATER PUMP BEARINGS BROKE AND THE FAN STOP TURNING SINCE BOTH ARE CONNECTED TOGETHER, HE SAID THE ENGINE MIGHT BE DAMAGE POSSIBLE DUE TO OVERHEATING. THERE WAS NO WARNING OF OVER HEATING ON THE GAGE, WATER DID NOT LEAK FROM THE PUMP. I CALL GM AND THEY TOLD ME TO TOW IT TO THE DEALER FOR DIAGNOSE AND THEY WERE CONSIDER MY CLAIM AFTER THE DIAGNOSE CHECK; THEY KNEW MY WARRANTY JUST EXPIRED IN JULY. I TOLD THEM THERE WAS KNOW WARNING OF ANY KIND EVERYTHING WAS FIND WATER PUMP BEARINGS JUST BROKE ALONG WITH THE FAN CLUTCH THIS SAMPLE PROBLEM CAUSE THE WHOLE ENGINE TO GO BAD. IF THERE IS GOING TO BE A PROBLEM WITH BEARINGS BROKEN ON THE WATER PUMP THERE SHOULD BE A WARNING OF THIS POTENTIAL PROBLEM. RIGHT KNOW I NEED HELP TO GET MY TRUCK FIX GM DENIED MY CASE TO FIX THE ENGINE. I BELIEVE GM KNOWS THERE IS A PROBLEM WITH THESE WATER PUMPS AND SERIOUS DAMAGE IT CAN CAUSE IF THEY FAIL. *TR
NHTSA ODI #10281206
52,000 miles · May 11, 2009
Engine And Engine Cooling
TL*THE CONTACT OWNS A 2004 CHEVROLET TRAILBLAZER. THE CHECK ENGINE LIGHT ILLUMINATED ON THE INSTRUMENT PANEL AND THE CONTACT TOOK THE VEHICLE TO THE DEALER; HOWEVER, THEY COULD NOT DETERMINE THE CAUSE OF THE FAILURE. THE LIGHT HAS BEEN ILLUMINATING EVER SINCE THE VEHICLE WAS PURCHASED, BUT THE FAILURE CANNOT BE LOCATED OR REPA…
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TL*THE CONTACT OWNS A 2004 CHEVROLET TRAILBLAZER. THE CHECK ENGINE LIGHT ILLUMINATED ON THE INSTRUMENT PANEL AND THE CONTACT TOOK THE VEHICLE TO THE DEALER; HOWEVER, THEY COULD NOT DETERMINE THE CAUSE OF THE FAILURE. THE LIGHT HAS BEEN ILLUMINATING EVER SINCE THE VEHICLE WAS PURCHASED, BUT THE FAILURE CANNOT BE LOCATED OR REPAIRED. THROUGH ONLINE RESEARCH, THE CONTACT DISCOVERED NUMEROUS COMPLAINTS REGARDING THE VEHICLE. THE FAILURE MILEAGE WAS 52,000 AND CURRENT MILEAGE WAS 56,000. UPDATED 06/08/09 *BF UPDATED 06/18/09.*JB
NHTSA ODI #10268391
55,000 miles · Dec 7, 2008
Engine And Engine Cooling
AIR CONDITIONER CONTROLLER WILL NOT WORK ON THE #1 SETTING. *TR
NHTSA ODI #10250994
88,000 miles · Nov 23, 2008
Engine And Engine Cooling
WE HAVE HAD A PROBLEM WITH OUR SERVICE ENGINE LIGHT COMING ON WITHIN THE PAST 2 WEEKS IN OUR 2004 TRAILBLAZER. AFTER GETTING IT DIAGNOSED IT IS BEING CAUSED BY THE FAN SPEED BEING TOO HIGH. AFTER DOING SOME RESEARCH THIS VEHICLE HAS HAD NUMEROUS REPAIRS FOR THE SAME ISSUE. WHY HAS GM NOT WARRANTED THIS!? WE HAVE GOTTEN CRAPPY SE…
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WE HAVE HAD A PROBLEM WITH OUR SERVICE ENGINE LIGHT COMING ON WITHIN THE PAST 2 WEEKS IN OUR 2004 TRAILBLAZER. AFTER GETTING IT DIAGNOSED IT IS BEING CAUSED BY THE FAN SPEED BEING TOO HIGH. AFTER DOING SOME RESEARCH THIS VEHICLE HAS HAD NUMEROUS REPAIRS FOR THE SAME ISSUE. WHY HAS GM NOT WARRANTED THIS!? WE HAVE GOTTEN CRAPPY SERVICE FROM THE DEALERSHIP AND WHILE OUR VEHICLE IS OUT OF WARRANTY NOW IT IS PAID FOR OUR WE WOULD HAVE GOTTEN RID OF IT ALREADY. *TR
NHTSA ODI #10249591
60,000 miles · Sep 29, 2008
Engine And Engine Cooling
MY 2004 TRAILBLAZER HAS BEEN HESITATING AND STALLING FOR ABOUT A YEAR AND A HALF. THIS OCCURS DAILY SOMETIMES SEVERAL TIMES A DAY. THERE ARE TIMES THE VEHICLE STALLS AND DIES. NO ONE HAS BEEN ABLE TO DETERMINE THE CAUSE. ABOUT SIX MONTHS AGO THE HEADLIGHTS QUIT. SINCE HAS BEEN REPAIRED. LAST WEEK THE DASH BOARD INSTRUMENTS QUIT …
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MY 2004 TRAILBLAZER HAS BEEN HESITATING AND STALLING FOR ABOUT A YEAR AND A HALF. THIS OCCURS DAILY SOMETIMES SEVERAL TIMES A DAY. THERE ARE TIMES THE VEHICLE STALLS AND DIES. NO ONE HAS BEEN ABLE TO DETERMINE THE CAUSE. ABOUT SIX MONTHS AGO THE HEADLIGHTS QUIT. SINCE HAS BEEN REPAIRED. LAST WEEK THE DASH BOARD INSTRUMENTS QUIT WORKING, FUEL GUAGE AS WELL. *TR
NHTSA ODI #10243945
32,000 miles · Aug 29, 2008
Electrical SystemEngine And Engine Cooling
I PURCHASED A USED 2004 CHEVY TRAILBLAZER IN FEBRUARY 08. IT ONLY HAD 23,000 MILES ON IT. WITH IN THE FIRST 2 WEEKS I HAD IT MY GAUGES STARTED GOING CRAZY. THEY WERE JUMPING AROUND ALL OVER THE PLACE. I TOOK IT BACK TO THE DEALER TO HAVE IT FIXED AND THEY TRIED TO CHARGE ME. FORTUNATELY I MUST HAVE COMPLAINED ENOUGH AND TO THE R…
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I PURCHASED A USED 2004 CHEVY TRAILBLAZER IN FEBRUARY 08. IT ONLY HAD 23,000 MILES ON IT. WITH IN THE FIRST 2 WEEKS I HAD IT MY GAUGES STARTED GOING CRAZY. THEY WERE JUMPING AROUND ALL OVER THE PLACE. I TOOK IT BACK TO THE DEALER TO HAVE IT FIXED AND THEY TRIED TO CHARGE ME. FORTUNATELY I MUST HAVE COMPLAINED ENOUGH AND TO THE RIGHT PERSON BECAUSE IT WAS REPLACED AT NO CHARGE TO MY SELF. I NOW AM HAVING MAJOR PROBLEMS WITH IT STALLING AND TRYING TO STALL. AFTER SEARCHING THE INTERNET I SEE THAT I AM NOT ALONE THERE ARE HUNDREDS OF COMPLAINTS ABOUT THIS PROBLEM. EVERYDAY UPON START UP IT IDLES VERY ROUGH AND IT TRIES TO STALL FOR A GOOD 10 MINUTES. IF I DON'T LET IT SIT AND IDLE BEFORE I DRIVE IT TENDS TO STALL. MY CHECK ENGINE LIGHT WILL FLICKER AT LEAST ONCE A DAY AND EVERY FEW DAYS MY REDUCED ENGINE POWER LIGHT WILL FLICKER. I DO NOT FEEL SAFE ANYMORE. WHAT IF I AM TRAVELING AND MY CAR STALLS AND I LOSE CONTROL AND FROM READING THE OTHER COMPLAINTS I AM AT RISK FOR MY AIR BAGS NOT DEPLOYING. IF IT IS A PROBLEM WITH THE PCM, I DON'T HAVE THE MONEY TO FIX IT!!!!! WHY SHOULD I HAVE TOO? I SEE THAT I AM NOT ALONE WITH THIS PROBLEM. WHY IS THEIR NOTHING BEING DONE ABOUT IT? WHY SHOULD US AS CONSUMER ALREADY PAYING ENOUGH FOR THESE VEHICLES BE RESPONSIBLE FOR THEIR MISTAKES? *TR
NHTSA ODI #10240160
40,000 miles · Aug 3, 2008
Engine And Engine CoolingFire
OUR 2004 CHEVROLET TRAILBLAZER WITH APPROX 40,000 MILES CAUGHT FIRE WHILE DRIVING APPROXIMATELY 40 MPH. WE NOTED SMOKE BEHIND THE CAR AND BEFORE WE COULD PULL OVER OTHER DRIVERS WERE YELLING TO US THAT THE CAR WAS ON FIRE. WE IMMEDIATELY GOT TO SIDE OF ROAD, TURNED OFF ENGINE AND A LARGE FIRE WAS COMING FROM THE HOOD. A GOOD S…
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OUR 2004 CHEVROLET TRAILBLAZER WITH APPROX 40,000 MILES CAUGHT FIRE WHILE DRIVING APPROXIMATELY 40 MPH. WE NOTED SMOKE BEHIND THE CAR AND BEFORE WE COULD PULL OVER OTHER DRIVERS WERE YELLING TO US THAT THE CAR WAS ON FIRE. WE IMMEDIATELY GOT TO SIDE OF ROAD, TURNED OFF ENGINE AND A LARGE FIRE WAS COMING FROM THE HOOD. A GOOD SAMARITAN RAN UP WITH A FIRE EXTINGUISHER AND PUT OUT THE FIRE THAT WAS APPROX 4 FEET HIGH FROM THE HOOD. ALL PASSENGERS SAFELY EXITED THE CAR AS SOON AS STOPPING AND DUE TO THE FIRE BEING EXTINGUISHED QUICKLY NO OTHER DAMAGE WAS DONE. THIS VEHICLE WAS RUNNING FINE WITH NO RECENT ISSUES OR SERVICE ON THE VEHICLE PRIOR TO THIS EVENT. WE HAVE NEVER HAD THE CAR SERVICED BY ANYONE OTHER THEN CHEVROLET DEALERSHIPS. WE WERE INFORMED BY THE TOW TRUCK COMPANY THAT THEY HAVE MANY 2004 CHEVY TRAILBLAZERS TOWED THAT HAVE CAUGHT FIRE. I HAVE SEEN SIMILAR EXPERIENCES DESCRIBED ONLINE BUT HAVE NOT FOUND IF THERE IS A TECHNICAL SERVICE BULLETIN RELATED TO THIS. *TR
NHTSA ODI #10236791
30,000 miles · Jun 28, 2007
Engine And Engine Cooling
AFTER COMING TO A STOP THE 2004 CHEVROLET TRAILBLAZER EXT STALLED. I BROUGHT IT TO THE SANTA MARIA HOME MOTORS TWICE. THE FIRST TIME THEY ADDRESSED THE PROBLEM WITH THE 30,000 MILE SERVICE AND SAID SEE IF IT HAPPENS AGAIN. THE TRAILBLAZER STALLED AGAIN SO THEY REPROGRAMED THE COMPUTER AND CHARGED ME $85 TO DO THIS. TODAY M…
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AFTER COMING TO A STOP THE 2004 CHEVROLET TRAILBLAZER EXT STALLED. I BROUGHT IT TO THE SANTA MARIA HOME MOTORS TWICE. THE FIRST TIME THEY ADDRESSED THE PROBLEM WITH THE 30,000 MILE SERVICE AND SAID SEE IF IT HAPPENS AGAIN. THE TRAILBLAZER STALLED AGAIN SO THEY REPROGRAMED THE COMPUTER AND CHARGED ME $85 TO DO THIS. TODAY MY WIFE WAS DRIVING THE TRAILBLAZER AND IT STALLED AGAIN. LIKE I HAVE TOLD THE SERVICE AGENT AT HOME MOTORS I WA S AFRAID THAT THIS WILL HAPPEN WHEN MY WIFE AND CHILDREN WERE CROSSING THE TRAIN TRACK, AND THEY COULD BE KILLED BY AN ONCOMING TRAIN. I WILL BRING THE TRAILBLAZER BACK TO THE DEALER TOMORROW. *AK
NHTSA ODI #10194907
42,000 miles · Jan 10, 2007
Engine And Engine CoolingPower Train
TL* - SOMETIME IN LATE SEPTEMBER 2006, WHILE DRIVING AT 65 MPH THE TRANSMISSION BEGAN TO SLIP. THE VEHICLE SOUNDED AS IF IT WANTED TO ACCELERATE, BUT COULDN'T. THE CONTACT'S VEHICLE CONTINUED TO HAVE THE FAILURE FOR ABOUT 10 SECONDS. THE VEHICLE ALSO HAD THE SAME TYPE OF FAILURE WHILE AT A STOP LIGHT. WHILE TRYING TO A…
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TL* - SOMETIME IN LATE SEPTEMBER 2006, WHILE DRIVING AT 65 MPH THE TRANSMISSION BEGAN TO SLIP. THE VEHICLE SOUNDED AS IF IT WANTED TO ACCELERATE, BUT COULDN'T. THE CONTACT'S VEHICLE CONTINUED TO HAVE THE FAILURE FOR ABOUT 10 SECONDS. THE VEHICLE ALSO HAD THE SAME TYPE OF FAILURE WHILE AT A STOP LIGHT. WHILE TRYING TO ACCELERATE THE VEHICLE'S SPEED DECREASED TO 5 MPH FOR ABOUT 20-30 SECONDS. ON 10/11/06 CONTACT TOOK THE VEHICLE TO THE DEALERSHIP. DEALERSHIP REPLACED THE EXHAUST CHECK VALVE. ON 10/17/06 VEHICLE CONTINUED TO HAVE THE SAME FAILURE AND THE ENGINE LIGHT WAS TURNING ON,. THE CONTACT TOOK THE VEHICLE TO THE DEALERSHIP WHERE THEY REPLACED THE OXYGEN SENSOR. THE CONTACT CONTINUED TO HAVE THE SAME INCIDENT WITH THE TRANSMISSION SLIPPING AND THE CHECK ENGINE LIGHT COMING ON. CONTACT TOOK THE VEHICLE TO THE DEALERSHIP ON 10/3106, AND THEY REPLACED THE VALVE BODY. IT CONTINUED TO HAVE THE SAME INCIDENT WITH THE TRANSMISSION SLIPPING, BUT THIS TIME THE ENGINE LIGHT WAS NOT SHOWING. HE TOOK THE VEHICLE TO THE DEALERSHIP ON 12/20/06, AND THEY STATED THAT THERE WASN'T ANYTHING WRONG WITH THE VEHICLE. THE CONTACT CURRENTLY HAS THE VEHICLE PARKED AT HOME AND DOES NOT PLAN TO DRIVE IT BECAUSE HE DOESN'T FEEL SAFE IN VEHICLE. *AK UPDATED 2/26/2007 - *NM
NHTSA ODI #10178305
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.