Which parts fail
Components named in complaints (battery, alternator, wiring, ignition, instrument cluster, infotainment).
Mileage when the problem started
Owner reports
Selected complaints filed with NHTSA by 2006 Toyota Highlander Hybrid owners, lightly cleaned up (personal details are redacted by NHTSA).
While driving home from work in normal free-flowing traffic conditions on the freeway, several lights came on the dash indicating brake issues including vsc, ABS, skid, parking brake light. Continued to cautiously drive home, brakes seemed OK. Had our non-dealer mechanic look at the brakes all were fine and had recently been replaced. He could not find a brake issue. Took to the local Toyota dealer and one code came up c1391 "abnormal leak in accumulator" and was told I needed a new brake actuator at the cost of $3273.00. Diagnostic cost $138.00. Additional information on diagnostic paperwork from dealer says, "check for DTC's found c1391, check for fluid leaks, could not find leaks, check accumulator pressure voltage (3.5 v), depressed pedal 4-5 times accumulator pressure drops below 3.0 v, recommend replace brake/ABS actuator". …
On 12/02/13 the brake light and vcs system light came on. The warning light also went on and a beep noise inside the cabin, brakes does not function (breaks not responding). I took the car to an authorized Toyota dealership. According to the dealer codes (c1241 low or high power supply voltage, c1256 accumulator low pressure, and c1391 abnormal leak in accumulator) must be replaced the actuator assy, b part no. 4405048190. Actuator was replaced on 12/28/13 at $1,495 with tax for $ 1,600 and labor cost of $333.84. Ust be replaced. On 05/25/15 again the brake light and vcs system light came on. The warning light also went on and a beep noise inside the cabin, brakes does not function (no break). I took the car to an authorized Toyota dealership for a diagnostic and I pay $64.20. Again they mentioned that for a second time the actuator assy, b part no. 4405048190 needs a replacement. …
My wife and I were travelling on I-95 (southbound) towards richmond, va. My wife was the driver. We were steadily travelling at a speed... Between 65 and 70 in the left lane (required speed limit). All of a sudden, with no warning, the panel lights started blinking and the power to the car was shut off. My wife was screaming because she was not able to control or effectively apply brakes. She tried and pulled car off the road barely and we pushed it off to a safe side. This could have resulted in a serious accident if we were travelling in the middle lane. The car was left overnight and towed to Toyota dealer. The dealer called back and gave a quote of $10000 because the Hybrid inverter have to replaced. I mentioned the recall on the inverter. The dealer said the recall does not cover my issue. There is a recall on your website -what action or recourse do I have. …
My wife was parked in front of our apartment building, idling with her foot on the brake, when our 2006 Toyota Highlander Hybrid suddenly accelerated and crashed into a gate. Before the car crashed, she repeatedly applied the brake and even put the car in park. The car did not stop. After the impact, the engine continued to rev and accelerate before finally stopping. This had never happened before. The body has been repaired, but per Toyota, nothing mechanical or electronic has been touched. Last week Toyota sent a specialist out to inspect the car and download data. We were present at the time, and 5 DTC codes displayed. The descriptions displayed on the investigator's lap top mentioned vehicle speed sensors on right wheel and left wheel, the emps, body ECU switch circuit and "low or high power supply voltage". The car was test driven, and no errors or codes were reported. …
Intermittently, while driving down the road, all of the dash lights come on, there is a high beeping sound, and the brakes stopped functioning properly. The brakes either need to be matched with extreme force or the brakes will slam by barely touching the brake pedal. Toyota acknowledges that this is an issue and offered a warranty extension to owners of this vehicle. I purchased the vehicle after the extension was offered and haven't had issues until recently. I am concerned for not only my safety but the safety of my family. I have been a Toyota fan for all of my adult life. However, after dealing with this issue and being quoted $2000 to fix it, I would offer advice to anybody or not to buy a Toyota or at least not a Toyota Hybrid. Buyer and driver beware!
There was fire in the inverter assembly. The wiring harness for the inverter and the transmission were completely cooked and melted. The professional opinion of a Toyota national engineer is that the generator in the trans axle surged and caused a fire melting the components. How can this go un-investigated with so many of these vehicles on the road. My family and I could have been burned alive or in a fatal crash due to this completely unsafe system. How can Toyota continue to say they are all about safety when they will not do anything about issues like this. They have sent me a $16,000 bill for this issue that is completely a product of their poor and unsafe vehicle.
I was pregnant and driving with 2 small children when the lights on my dashboard came on about vsc and a loud ringing happened and then I tried to brake at the stop light and they were so difficult to push I barely stopped in time to avoid an accident. Was told it was the ABS system and that Toyota is aware of this but put stipulations on an extended warranty rather than recall so it's too late for most to get fixed and be covered. This is a huge safety issue and expensive fix Toyota needs to stand behind.
Tl* the contact owns a 2006 Toyota Highlander Hybrid. The contact stated that while the vehicle was parked, an unknown door failed to open without warning. The contact mentioned that when the door was opened, the contact smelled a fuel odor. The vehicle was taken to an independent mechanic where it was diagnosed that the Hybrid battery exploded and needed to be replaced. The vehicle was not repaired. The manufacturer was not notified of the failure. The failure mileage was 110,000. Updated 04/13/16
Tl* the contact owns a 2006 Toyota Highlander Hybrid. The contact stated that the vehicle did not start and the Hybrid warning indicator illuminated. The contact also stated that the vehicle was repaired three previous times by naguabo auto Toyota (carretera 31 km 3.9, naguabo, pr 00718) regarding the Hybrid module. The vehicle was not repaired again. The manufacturer was not notified of the failure. The approximate failure mileage was 150,000.
I was driving the vehicle and heard a loud popping noise on the way to the dealership for recall work. Once the technician opened the inverter case we found the wiring harness for both the inverter and transmission were completely melted and cooked due to a fire inside the inverter. I am now looking at a $15000 repair bill with Toyota and luckily my family and I were not burned alive or in an accident resulting in fatalities.
Related recalls
Electrical system
Toyota is recalling certain model year 2006-2007 highlander hybrid and Lexus rx400h passenger cars manufactured from February 16, 2005, through August 30, 2006. A module inside the inverter module May contain inadequately soldered transistors that during high-load driving, May be damaged by heat caused by the large current.
Remedy: Toyota/Lexus mailed an interim owner notification on July 19, 2011 to advise owners of this recall and the fact that they will receive a future notice when parts become available to complete repairs.
NHTSA investigations
Unintended and Uncontrolled Acceleration
On February 16, 2010, NHTSA's Office of Defects Investigation (ODI) opened RQ10-003 to determine whether the scope of prior Toyota recalls relating to potential unintended acceleration were sufficiently broad, including, among others, Toyota recalls 07E-082, 09V-388, 10V-017, and 10V-023.NHTSA also requested information regarding potential electronic causes of unintended acceleration in Toyota and Lexus vehicles.I.
Pedestrian alert sounds
NHTSA received a petition on or about July 18, 2022, requesting that Federal Motor Vehicle Safety Standard (FMVSS) 141 be applied to all electric and hybrid vehicles operating in the United States. The petition can be reviewed at NHTSA.gov under ODI Number 11486072. FMVSS 141 establishes performance requirements for pedestrian alert sounds for motor vehicles.
Electrical complaints in other Highlander Hybrid years
Frequently asked questions
How common are electrical problems on the 2006 Toyota Highlander Hybrid?
NHTSA has 74 complaints about the electrical system of the 2006 Toyota Highlander Hybrid, 20% of the model year's 370 complaints. The component named most often is 12v/24v/48v battery (2 mentions).
Is there a recall for 2006 Toyota Highlander Hybrid electrical problems?
Yes — NHTSA recall 11V-342 (electrical system, Jun 29, 2011). Recall repairs are free at authorized dealers.
At what mileage do 2006 Toyota Highlander Hybrid electrical problems start?
Half of the complaints with a recorded mileage happened before about 115,000 miles, and 8% before 25,000 miles.
Is it dangerous?
Owners linked 1 crash, 2 fires and 0 injuries to electrical system problems on this model year. If you notice symptoms, have the car checked before driving further.
Source: U.S. National Highway Traffic Safety Administration (NHTSA) — owner complaints through October 20, 2026, recalls and defect investigations; fuel economy from the EPA. Complaints are unverified reports and are not proof of a defect. How we rate model years.