There are 4 stored owner reports matching the electrical system leading-label group for the 2003 Toyota Sienna in our NHTSA-sourced dataset. These are unverified consumer reports and may not reflect confirmed defects.
This group counts stored reports whose component label starts with one of this site's matching prefixes, ignoring case. Each matching report counts once within the group. Components mentioned later in the label or only in the narrative are not searched. How component counts work
Loaded 4 of 4 matching reports.
Open the full vehicle complaint log (all categories)TL* THE CONTACT OWNS 2003 TOYOTA SIENNA. THE CONTACT STATED THE INSTRUMENT PANEL ON THE VEHICLE DOES NOT WORK AND WHEN THE VEHICLE EXCEEDS 30-40 MPH, IT SLOWS DOWN AND THE ALL OF THE WARNING LIGHT ILLUMINATE. THE LOCAL MECHANIC REPLACED THE SENSORS FOR THE COMPUTER, BUT THAT DID NOT CORRECT THE PROBLEM. THE VEHICLE WAS NOT INSPECTED BY A DEALER. THE FAILURE MILEAGE WAS UNKNOWN, BUT THE CURRENT MILEAGE WAS 74,000.
ON 09/04/09, MY 2007 TOYOTA COROLLA COMPUTER FAILURE RESULTED IN POWER LOSE WITHIN SECONDS AT TRAFFIC LIGHT AND STOPPED. THIS HAS BEEN REPORTED TO NHTSA ON 09/08/09 AND COMPLAINT # IS 10283338. HOWEVER, MY ANOTHER TOYOTA CAR ALSO HAD COMPUTER FAILURE IN NOV 2009. ALL OF MY 2 TOYOTA CARS HAD COMPUTER FAILURE IN 2009. I BELIEVE THE TOYOTA CARS HAVE COMPUTER PROBLEMS AND I SUGGEST NHTSA TO OPEN INVESTIGATION. 2003 TOYOTA SIENNA COMPUTER FAILURE RESULTED ENGINE LIGHT ILLUMINATED AROUND NOV. 21, 2009. *TR
DESIGN DEFECT ON HORN FOR 2003 TOYOTA SIENNA. 1. ONLY ONE OUT OF THE TWO HORN BOTTOM CONTACT PLATES IS ELECTRICALLY CONNECTED. 2. THE STEERING WHEEL IS NOT DIRECTLY GROUNDED BY THE SPIRAL CABLE. GROUND FROM SPIRAL CABLE IS USED FOR THE CRUISE CONTROL AND REMOTE RADIO CONTROL. THE GROUND FOR THE HORN IS ONLY INDIRECTLY GROUNDED THROUGH THE SHAFT. I JUST HAVEN'T USED THE HORN UNTIL RECENTLY. HORN IS NOT RELIABLE. SOME TIMES IT DOESN'T WORK. ESPECIALLY WHEN PRESSING ON THE LEFT SIDE OF THE HORN PAD. MANY PEOPLE HAVE BEEN COMPLAINING OF HORN MALFUNCTION ON TOYOTA CAR OWNER BOARDS AND TOYOTA NOT BEING ABLE TO REPAIR IT PROPERLY (REPLACING SPIRAL CABLE AND RELAY), ON MY VAN, THE CONNECTION TO THE RELAY IS MISSING (NEVER INSTALLED) ON THE LEFT SIDE CONTACT PLATE AND ACTIVE GROUND IS MISSING. I HAVE NOT FIGURED OUT HOW TO FIX THESE SAFETY DEFECTS. *TR
TOYOTA SIENNA 2003 BRAND NEW CAR THE BATTERY LEAK AND CAUSE THE RADIATOR DAMAGE DEALER STATE THAT THIS IS NOT A WARRATY REPAIR. THIS IS A WARRANTY REPAI AND THATS WHAT THE LEMON LAW SAYS . THE DEALER WHICH IS BAY RIDGE TOYOTA AND MAN WHO IS MANAGER TOM SCARPACCI SAYS THIS IS NOT WARRANTY REPAIR. *AK
Complaints are unverified consumer reports submitted to NHTSA. A high complaint count may reflect vehicle popularity, not defect severity. Data sourced from NHTSA public records.
NHTSA source checks for this vehicle year
Checks are recorded separately for each dataset, not for the whole page. Dates use UTC. A missing check date does not mean no records exist.
Vehicle import recorded: Apr 29, 2026. This is the stored import date, not confirmation that every source was successfully refreshed.