2006 Toyota Prius Electrical System Problems

The light up display for the odometer, fuel gauge, and speedometer does not always light up. When it is not lit, the cruise control and any warning and informative alarms/lights also do not work. This is a well-known issue among owners of these cars, related to the capacitors on the circuit board for the display being defective, and there is extensive documentation of it online. It may also have had a technical service bulletin released for the issue, but I'm not entirely sure. The light goes out intermittently and is not always consistently out. I did mention it to the service personnel when I took it in to get recalls repaired recently, and they didn't seem surprised or unaware of the issue. I did not ask them to diagnose or fix it, as I know I can get it done for a better deal elsewhere.

The following describes a near total failure of the brake system that accompanies and is triggered by routine aging of the battery. I believe this applies to multiple model years and editions of the Prius, based on reports by other owners on owners' discussion groups. I believe this should have the highest severity level. Here is what happens: An alarm is sounded, several warning lights ABS, VCS appear, and soon after that, the front brakes stop working. The rear brakes then prove ineffective and lock up. The happens with high frequency under any of the following conditions: (a) as the battery approaches 3yrs age, (b) it is excessively cold outside. (c) there is a higher than typical load on the 12V system from any of a variety of reasons. After installing a fresh new 12V battery, the above happens with much less frequency. There no warning on the dashboard to indicate that the condition of the 12V battery is not safe for operation of the vehicle. It seems clear that the route cause is that the brake control unit is configured within inadequate tolerance for the normal aging of the 12V battery, compounded by the absence of warning on the dash. This probably traces back to a poorly chosen LDO voltage regulator in the design of the brake control unit. Recommendation: Review the electrical designs for the brake control unit, all model years, replace as needed and update the dash board computer to provide warning when the battery condition is not sufficient for safe operation of the vehicle. I further recommend that this be done with all due haste, as the condition is quite dangerous. Qualifications: PhD Chemical Physics and Electrical Engineer

One afternoon, in the Summer of 23, I entered my Toyota Prius to run some errands. Once I proceeded to power on the car, none of the dashboard lights illuminated. This included the gas gauge, speedometer & transmission indicator. Fortunately, I was only driving a few blocks down the road from my residence as I live in a small rural town with little congestion, little traffic and mostly two-lane roads. I can't imagine this occurring in a much larger metropolitan city. When I arrived at my destination, I discovered that my Prius wouldn't shut off. This dashboard malfunction was preventing the Toyota from powering off. I quickly completed my errands with my vehicle running during this entire ordeal. Finally, when I returned home, I frantically researched on YouTube regarding this issue and discovered many others who also were having these no-illuminating-dashboard problems. Some YouTubers offered workarounds but the solutions will be temporary as the problem will eventually worsen until the Prius owners have no working dashboard lights. From the way I understand it, this problem is nothing more than a small computer board that's behind the speedometer and this computer board has a small diode that tends to burn out on all kinds of Toyota Priuses when it reaches around 150,000 miles.

I was Driving down the main road at night time in my 2006 prius and the headlights both went out and all most caused a crash. I pulled over turned my car off then back on and the headlights came back on so i started driving home. After driving a couple blocks i was pulled over by the police because my drivers side headlight was off. Luckily he let me go with a warning, but i work at night and am losing money daily because of this problem. I sent toyota a email and no answer. There has been many electrical problems with this car and the speedometer still says i am deiving 34 to 35 mph while i am actually only going 30mph. I think that toyota should fully fix the problems in thos car. Its amazing there can be so much wrong with a vehicle and they not have to replace the vehicle with a vehicle that works or fix all the problems and give me a loaner vehicle. I will upload a picture of what the toyota dealership nearest to me wanted just to replace 1 bulb ans the balast wires going to the light for one loght they want $211.34 and that is just for the bulb and wire. For there time they said each bulb and wire would be around $500 worth of repair time to pay for them to put the new light and wire in so for one lightbulb with rhe wire would be about $800-$1000 for the dealership to replace the parts, so basically $2000 to replace both light bulbs and the wires and pay the toyota company to put them in. If you look at the estimate it is for 1 bulb and 1wire and that would be the price if i put them in and if i only wanted the parts. So $211.34 then i would have to double it because i would need 2 bulbs and 2 wires. Then i would have to add another $1000. That is $500 for labor for them to put the bulbs in per each bulb and wire and they said its not guaranteed it will fix the problem. So that is $422.68 for parts and they said somewere around $500 for them to install each bulb and wire and after it might not even fix the problem. So that is $2422.68 to maybe fix the problem.

Randomly the instrument panel (dashboard) does not turn on with the vehicle.

Hi, After being parked for about 1.5 hrs my back seat on the drivers side caught on fire. I understand this is where a battery is and that newer cars of this brand have had recalls for this problem.

The contact owns a 2006 Toyota Prius. The contact stated that the vehicle intermittently failed to shut-off as needed with several unknown warning lights illuminated. The contact had taken the vehicle to the dealer on three separate occasions and the mechanic was able to either disconnect the battery or shut-off the vehicle as designed. The manufacturer had been notified of the failure and informed him that the vehicle was out of warranty and that there were no recalls on the vehicle. The contact filed a case with the manufacturer. The vehicle was not diagnosed nor repaired. The approximate failure mileage was 160,000. Consumer stated Toyota is refusing to responsibility even with extended warranty if problem occurred after 2012.

Discovered through failures repeated to dealers that certain items (Brakes, dashboard, et. al.) were recalled by Toyote. Never received recall notices. Contacted Toyota who demanded the vehicle be taken to dealer and now refuses to do anything. Have complete documentation to attach to this communication. Essentially: Dashboard failed, brakes failed when auto in operation. Likely there are UNKNOWN additional recalls, etc. of which we were not noticed

KNOWN PROBLEM WITH COMBINATION METER - FOUND IT SEARCHING ONLINE ONCE I REALIZED THIS WAS THE PROBLEM. I BOUGHT MY CAR USED AND SINCE IT IS NO LONGER COVERED BY TOYOTA, IT DIDN'T COME UP IN SEARCH. HAVING ISSUES WITH THERE BEING NO DISPLAY ON THE DASH AND VEHICLE NOT SHUTTING OFF FOR THE ENTIRE TIME I HAVE HAD THE CAR. IT ONLY HAPPENS INTERMITTENTLY. THIS IS A SAFETY ISSUE FOR SURE! CAN'T SEE SPEED, GAS, GEARS...ANYTHING ABOUT CAR WHETHER CAR STATIONARY OR MOVING.

HEADLIGHTS CONSTANTLY GO OUT. RESEARCH ONLINE PROVES PRIUS VEHICLES WITH HID BULB SYSTEMS HAVE BALLAST ISSUES CAUSING CONSTANT BLOWING OF EITHER BULBS OR BALLAST FAILURE. NOT ONLY IS SAFETY CONSTANTLY COMPROMISED, BUT IT IS ILLEGAL WHEN A HEADLIGHT GOES OUT DRIVING DOWN THE ROAD.

ACCORDING TO THE TOYOTA DEALERSHIP WHERE I HAVE MY CAR MAINTAINED, MY 2006 PRIUS IS IN NEED OF A NEW MOTHERBOARD. APPARENTLY THERE WAS A RECALL ON THIS PRIOR TO SO MANY MILES ON THE VEHICLE BUT I HAVE MISSED THIS DEADLINE AS MY CAR DID NOT SHOW THESE SYMPTOMS PRIOR TO THE CUTOFF.. MY PRIUS WHEN TURNED ON DOES NOT TURN ON THE DASH BOARD FEATURES SO I HAVE NO IDEA HOW FAST I AM DRIVING. ONCE I REACH MY DESTINATION I AM UNABLE TO TURN MY CAR OFF. THE POWER BUTTON DOES NOT RESPOND, USUALLY FOR SEVERAL HOURS. IN THESE CASES I USUALLY LEAVE MY CAR ON IN THE PARKING LOT WHERE I AM AND RETURN OVER THE NEXT SEVERAL HOURS TO CHECK ON IT. IT TENDS TO TURN OFF AFTER TAKING THE CAR FOR A LONG DRIVE SEVERAL HOURS LATER. THIS OCCURS ABOUT TWICE A MONTH NOW.

THE WATER PUMP WENT OUT CAUSING THE HYBRID BATTERY TO DIE. PRESSING THE BREAK IS SUPPOSED TO RECHARGE THE BATTERY BUT THE BATTERY IS NOW COMPLETELY GONE

I WAS DRIVING ON A HIGHWAY 95 SOUTH, ALMOST TO DELAWARE, AT NIGHT IN THE RAIN, AFTER 4 HOURS ON THE ROAD, EVERYTHING STOPPED WORKING. I COULDN'T ACCELERATE, I HAD NO BRAKES, AND EVENTUALLY EVEN MY LIGHTS WENT OUT. THE ENTIRE ELECTRICAL SYSTEM WAS OUT. I WAS IN HEAVY TRAFFIC, AND DON'T EVEN KNOW HOW I GOT OFF THE HIGHWAY, AND TO A GAS STATION. THE TOW TRUCK DRIVER COULDN'T EVEN JUMP THE BATTERY ENOUGH TO GET THE CAR IN NEUTRAL, AND HAD A DIFFICULT TIME GETTING IT UP ON THE FLATBED TO TOW IT HOME. I COULDN'T EVEN LOCK THE DOORS. I HAD A NEW KEY MADE AT THE DEALERSHIP ON 10/17/19 AND I WAS USING THAT KEY FOR HOURS DRIVING TO CT AND A COUPLE OF DAYS LATER I WAS HALF WAY HOME WHEN EVERYTHING IN THE CAR STOPPED WORKING. I WAS TOWED TO MY HOME IN MD BECAUSE I NEEDED TO BE ABLE TO UNPACK MY CAR AND COMPUTER BEFORE TAKING IT TO THE DEALERSHIP. WHEN THE SECOND TOW CAME THE NEXT DAY, I HANDED HIM THE KEY BY THE FRONT DOOR, WHICH WAS MY OLD KEY, AND HE WAS ABLE TO GET THE CAR IN NEUTRAL RIGHT AWAY, AND AT THE DEALERSHIP THE CAR WORKED JUST FINE. THE ONLY DIFFERENCE WAS THE NEW KEY. THE TECHNICIAN FOUND THAT "THE IMMOBILIZER ECU HAS AN INTERMITTENT OPEN CIRCUIT FAILURE, CAUSING THE KEY TO BE SEEN AS UNAUTHORIZED AND STALL THE ENGINE." FROM JIM COLEMAN TOYOTA. APPARENTLY THERE IS A PART OF THE COMPUTER SYSTEM THAT SHUTS OFF ALL SYSTEMS IF IT DETECTS AN "UNAUTHORIZED" KEY--I.E. IF IT BELIEVES THE CAR IS BEING STOLEN. IT SEEMS TO ME THAT THIS IS A VERY DANGEROUS PROGRAM IN THIS CAR. I HAD BEEN USING THAT NEW KEY FOR SEVERAL DAYS, AND HAD NO PROBLEM, BUT FOR IT TO DECIDE IN THE MIDDLE OF THE HIGHWAY AFTER HOURS ON THE ROAD THAT THE KEY WAS A FAKE, I COULD HAVE BEEN KILLED OR I COULD HAVE KILLED SOMEONE ELSE. I WOULD MUCH PREFER THAT MY CAR BE STOLLEN THAN THAT SOMEONE MIGHT GET KILLED BUT SHUTTING OFF EVERYTHING WHILE IT WAS ON THE ROAD.

BOTH OF MY HEADLIGHTS WENT OUT AT THE SAME TIME THE OTHER DAY NOW THE FACT THAT BOTH OF THEM WENT OUT AT THE EXACT SAME TIME ALREADY TELLS ME THAT ITS NOT THE BULB,BALLEST OR ANYTHING OTHER THEN AN ELECTRICAL ISSUE BECAUSE EVERYONE IS HAVING THIS PROBLEM AND THEY HAVE CHANGED BOTH BALLASTS AND BULBS AND THE SAME THING HAPPENED OVER AND OVER AGAIN, PLEASE MAKE THIS A RECALL BECAUSE IT IS VERY UNSAFE

TOYOTA REFUSES TO REPLACE THE COMBINATION METER IN MY VEHICLE ALTHOUGH IT ONLY HAS 110K MILES ON IT. THEY HAVE ACKNOWLEDGED MY VEHICLE WAS INCLUDED WITH THE BATCH OF MODELS THAT HAVE THIS KNOWN ISSUE UNDER 2004-2009 TOYOTA PRIUS COMBINATION METER WARRANTY EXTENSION ZTV, BUT WILL NOT COVER. THIS IS NOT RIGHT FOR A CONSUMER TO BE ON THE HOOK FOR TOYOTA'S QUALITY ISSUE. THIS IS A SIGNIFICANT SAFETY ISSUE AND SHOULD BE UNDER A FORMAL RECALL.

MY HV BATTERY HAS A PROBLEM. THE RED TRIANGLE SHOWED WHEN THE CAR MILLAGE WAS ONLY 118000M. I CHECKED WITH SERVCO AND REPLACED ONE CELL OF THE HV BATTERY. HOWEVER, THE RED TRIANGLE SHOWED AGAIN, AND CODE READER FOUND ANOTHER DAMAGED CELL. THAT WOULD BE A POSSIBILITY THAT THE WHOLE HV BATTERY WAS DAMAGED.

KNOWN PROBLEM WITH COMBINATION METER - FOUND IT SEARCHING ONLINE ONCE I REALIZED THIS WAS THE PROBLEM. I BOUGHT MY CAR USED AND SINCE IT IS NO LONGER COVERED BY TOYOTA, IT DIDN'T COME UP IN SEARCH. HAVING ISSUES WITH THERE BEING NO DISPLAY ON THE DASH AND VEHICLE NOT SHUTTING OFF FOR THE ENTIRE TIME I HAVE HAD THE CAR. IT ONLY HAPPENS INTERMITTENTLY. THIS IS A SAFETY ISSUE FOR SURE! CAN'T SEE SPEED, GAS, GEARS...ANYTHING ABOUT CAR WHETHER CAR STATIONARY OR MOVING.

I WAS DRIVING NORMALLY AND SUDDENLY A CONTINUOS BEEP WAS THERE,I TRIED TO STOP A NO BRAKES.I WAS ABLE TO STEER MY CAR TO A SAFE PLACE.THEN USED A TOLL SERVICE AND TOOK IT TO MY TOYOTA DEALER.IN A SHORT TIME THEY TOLD ME THEY TOLD ME THE COMPUTERIZED BRAKE SYSTEM WAS DEFECTIVE AND THE JOB WILL COST ME $2250.00 I CAN NOT AFFORD. I TOLLED THE CAR BACK TO MY HOUSE .LATER I FOUND THAT THERE HAD BEEN A RECALL FROM TOYOTA.I WAS NEVER NOTIFIED ALTHOUGH I TOOK MY CAR THERE FOR REGULAR CHECKUPS. NOTE: MY CAR WAS IN MOTION AND PREVIOUS TO INCIDENT I HAD DESCENDED A STEEP HILL. I CONSIDER MYSELF LUCKY ON THAT DATE,THREE MINUTES EARLIER I WOULD HAVE BEEN IN GREAT DISTRESS TRYING TO STOP MY TOYOTA PRIUS.

SOMETIMES AS I DRIVE THE VEHICLE, AFTER A WHILE, EITHER ONE OF THE HEADLIGHTS TURNS OFF RANDOMLY. I DON'T ALWAYS NOTICE WHEN IT HAPPENS, OTHER THAN WHEN PULLING UP BEHIND ANOTHER VEHICLE AT A STOP LIGHT AND NOTICE THAT THERE IS ONLY 1 HEADLIGHT REFLECTION COMING FROM MY VEHICLE. THEY BOTH WORK NORMALLY IF I TURN THEM OFF AND ON AGAIN.

COMBINATION METER IS GOING OUT ON THE CAR. THIS CONTROLS THE DASHBOARD LIGHTS, MEANING THAT I CANNOT SEE HOW FAST I AM GOING OR IF THERE ARE ANY GAUGES OR SENSORS LIT UP ALERTING ME TO A PROBLEM WITH THE VEHICLE. TOYOTA HAD AN EXTENDED WARRANTY ON THIS BUT IT HAS NOW EXPIRED AND THEY WANT $1000 TO FIX IT.