For some time the headlights on our 2007 Toyota Prius have been behaving strangely, with one or the other going out intermittently, then later coming back on. Last weekend while driving at night on dark, narrow, twisty mountain roads, they both suddenly went out. The car can not be driven at night due to the risk of headlamp failure and crash. Toyota dealers quote $1000-plus cost to repair an obvious design flaw with serious safety implications.

- Silver Spring, MD, USA

When driving with the headlamps on, one headlamp (usually the driver's side but it has occurred which the passenger side as well) will go out. If I turn the lights off and turn them back on the both lights will work again. This is intermittent and I can't make it happen. At my last service they could not reproduce the problem and looked at me like I was nuts. I live in the country and do a lot of night driving. I am beginning to notice this happening on a weekly basis.

- Placerville, CA, USA

Toyota Prius headlamps are intermittent. Toyota dealer replaced the bulb but it's still intermittent.

- Bethesda, MD, USA

Have had problems with 2007 Toyota Prius several months. Different times neighbors and other drivers pointing out headlight that was out. Turned them back on and thinking nothing was wrong with my headlights when I got out of the car and looked but noticed they had been dimming trough time. Could not tell which lights were out because then they would work. 2 near misses when other driver noticed my headlights were out but due to heavy traffic was able to drive due to other drivers lighting. Driving the other night with family in car and lights went out completely. Panicked and turned them back on and they came on but still dimmer. Coming home from work the other day and then stopped by police in which I explained my headlight problems and informed them that my plans were to take Prius to dealership. After this incident and driving at night with my family in car this was my final step. Took 2007 Toyota Prius 10/20/09 to dealership and they said it would cost me replacing the headlight. Of course at my cost. They performed diagnostic testing and could not find any problems other than the headlights needed to be replaced at a cost of several hundred dollars.

- League City, TX, USA

I have a 2007 Toyota Prius. The driver side head light goes out now and then as I am driving. It is unpredictable. If I turn the lights off and then back on, the light works again. It has been going on for 2 months. Now the other light is doing the same thing.

- Compton, CA, USA

Hid headlight on driver's side went out.

- Irvine, CA, USA

The right headlight went out on my 2007 Prius that has 40K miles on it. I didn't know the headlight was out. It was pointed out to me at the time of routine maintenance. I don't know how long I've been driving without a headlight. There's no warning signal in the car to alert me to the problem. I had the bulb replaced and it is working now, but I have since learned that this problem is not uncommon and is likely to recur so I'm concerned about it.

- Santa Monica, CA, USA

2007 Toyota Prius intermitant headlamp issue.

- Lindsay, TX, USA

I am the owner of a 2007 Toyota Prius. I am having problems with both headlights. My headlights will turn off every time I drive. Most of the time just one will go out. I can turn the switch off, then back on and the headlight will work for a short time and go out again. Only a few times have they gone out at the same time, very scary situations. I have done research online and am not the only Prius owner with this problem.

- Modesto, CA, USA

Hid headlamps failure. Driver side headlamp was going out randomly in August 2009. Vehicle is in warranty (20K miles) and dealer replaced bulb at no charge. In October the same problem began to occur on the passenger side. Again, the dealer replaced bulb at no charge. These bulbs are very expensive and difficult to replace and should last longer than 20K miles.

- Seattle, WA, USA

Head lights failed to work while driving at night.

- Waterbury, CT, USA

2007 Prius headlights - both go out, intermittently.

- Falls Church, VA, USA

2007 Prius started driving with headlights on. Drove from a well lit area with many street lights into an without any overhead lighting. Realized that the lights were not operating, while I was trying to determine what the problem was, looking at the headlight switch, I veered into an adjoining lane, luckily there were no vehicles in that lane. Eventually I turned the lights off and then back on again and they worked properly. Now the lights randomly turn off, passenger or driver side, while driving. I continually check the lights and turn them off and on to restart the lights. I have not had the lights fixed, I am waiting for Toyota to issue a safety campaign and to extend the warranty on this issue.

- Cincinnati, OH, USA

I have a 2007 Toyota Prius, and the driver's side headlight has been giving me problems for about the last 20K miles(50-70K). Toyota dealer said it would cost over $400 to replace the bulb, but I can turn the lights on and off to make it light up again. Seems like this is an electrical problem and not the bulb. When searching for a cheaper alternative, I ran across how many of the Prius are having the same problem. I live in a very rural area with curvy winding roads getting home in the evening. When that light cuts out I can hardly see the road. I don't know how this isn't a safety issue, especially when it could happen to both as I read has happened with others.

- Collierville, TN, USA

Intermittent failure of driver's side headlight. The light will come back on if the light switch is turned off and then back on, and will remain on for a an unpredictable period of time, some times as long two weeks before failing again. Toyota has advise me to bring the vehicle to a service facility when the light is out, but the light fails on weekends, holidays, or late at night when the dealership is not open. An internet search disclosed that this headlight failure is a fairly common defect in 2007 Prius.

- El Paso, TX, USA

Head lights on 2007 Prius with 59987 miles keep going out and you have to turn them off to get them to come back on. Dealership says it is going to cost $826 plus tax to fix the problem even though I have the platinum extended warranty.

- Milton, WV, USA

Front passenger headlight intermittently goes on and off with no reason. If the other headlight would burn out, I would be left in the dark. Replaced headlight and computer sub assembly $514 old part not available the day after this was repaired, the other headlight started doing the same thing! suspicious?

- Charlotte, NC, USA

I bought a 2007 Toyota Prius on August 1, 2007. I didn't have any issues with my car until August of 2008 when I started having issues with my headlights and tail lights (they would go off and then when I turned the lights off and flipped back on, they would come back on again). Twice while driving at night, all of my lights went out (headlights, tail lights and dash board lights)! I brought car into dealer and they didn't know what was wrong but replaced the headlights (to the tune of $1200 a piece). I didn't have trouble with my headlights after than until this year (August of 2009). My passenger headlight is going out and then flipping back on for a bit (although the bulb seems dull) when I turn lights off and then back on again. The problem is they won't stay on and it seems insane to pay $2400 a year for what obviously seems to be a vehicle defect; not to mention the safety issue of only having 1 headlight that works or tail light and dashboard lights going out while driving at night!

- Brainerd, MN, USA

The driver's side headlight turns off while driving. If I turn it off and back on, it will come back on, but it will only remain on for a short period of time. The dealership says that it is a problem with the computer that controls the hid headlights.

- Sandy, UT, USA

My 2007 Prius with 36,655 miles experienced the intermittent headlamp failure. Drivers headlight would randomly go off, but work fine other times. Eventually, it failed completely. I contacted my local Toyota dealerships service department. Their diagnosis determined circuit check revealed an internal short in headlamp ECU (electronic control unit) caused bulb to short. Replaced ECU and bulb. Operational test verified repair. Repair and parts covered under goodwill policy. The installed parts note part #90981-20015 bulb, hid and 81107-47150 computer sub-assy. My regular mechanic said that the ECU is equivalent to an igniter, which regulates voltage and current going to the headlamp, similar to a fluorescent ballast. My mechanic said the ECU is covered under the 3 year / 36K warranty. My replacement was covered at no charge under a "goodwill policy" because I was only 655 miles over 36K. (the initial headlamp failure occurred when I was out of town & mileage less than 36K.) the Toyota service manager stated off the record that service managers can internally approve such replacements up to 70K miles. However, those in the 80-100K mile range will likely not be approved. I attempted to convince them to also replace the passenger side headlamp as a preventive measure, but they refused. I"M sure it"S a ticking time bomb. With 42,554 current miles, both headlamps now work correctly. This is a known issue with the Toyota Prius and should be recalled! someone could be killed or seriously injured with random headlamp failure at night or in poor visibility conditions. And even if it weren't a dangerous situation, it is a known defect which they are aware of and responsible!

- Peachtree City, GA, USA