hi. i have a question regarding my 2006 prius. when i am driving, my headlights will just all of a sudden go out. doesn't matter whether on low or high beams. usually 1 at a time, either one, but on occasion both at once. all it takes to get them back on is to flick light switch on and off. getting worse as car gets older. question is, it seems to be a ballast problem (happening more that 1 year and car has always been out of warranty). is this common. are ballasts expensive. dealership said $500+. any help. thanks.
jim

 

If you are willing to do it yourself, there are books, avoid Chiltons, that cover the process. Alternatively, you can get the Toyota maintenance manuals, get the part, and save the labor. Another option is to get the parts from a salvage. The problem with these approaches is speed and quality.

In engineering we say, pick two:

• Good
• Fast
• Cheap

Bob Wilson

 

It's a known problem with HIDs in your model year. There were problems with both the ballasts and with bulbs. The ballasts are not easy to replace. You have to remove the fender liner, as I recall. You can get the parts online for a little less. There are a few Toyota dealers selling parts online.

 

I started developing this problem too with my 2008 Prius Touring. The drivers side headlight would go out periodically. Being (slightly handy) I decided to look at the headlights myself.
I discovered that the wires leading to the headlamps were Crimped and Bent Downward.
So I carefully pulled them up so they were straighter, and have NOT had problem since.
Apparently, the juice to the headlamps was being somehow stopped by the crimped wires?

This may or may not work for you, but sure is an inexpensive approach to try before buying expensive parts. Although another poster made reference to ballast/bulb problems that are known to exist for your year Prius.

You might also want to check to see if any TSB's exist about the problem for your car year?
If so, your dealership Should Repair the Problem For You.

Your dealership you purchased the car at, should have that information available.

Good Luck, Robert

 

HID ballasts are probably one of the MOST sensitive devices you have on the car with regards to battery voltage. A low battery voltage, or low voltage at the ballasts, could be your problem.

Remove the battery posts, clean and burnish them. Check both ends of the battery cables for tightness. There is almost ALWAYS a HEAVY duty grounding strap, battery current carrying "grounding" strap, between the engine and the body structure, often from the rear of the engine to the metal firewall. Make sure both ends of that are tightly connected.

If that doesn't solve your problem that check the battery condition, charge state, and then the charging circuit itself.

 

Does the HID light system get its voltage directly from the 12V auxiliary battery? How do you check the charging circuit on a 2nd gen Prius which charges from the HV battery?

 

Folks, do not pay for this out of your pocket.

Please read this thread for solutions.

Welcome to the club: http://priuschat.com/forums/care-mai...t-problem.html

Please file a complaint here: http://www-odi.nhtsa.dot.gov/ivoq/

 

The 12V battery and charging circuit are "one" when the car is in "ready", so you can't say the power comes from either, as it comes from both. The system runs at 13.8VDC, and gets its' power from the traction battery (the high voltage one). There is no 12V alternator in the Prius.

You can test it with a good voltmeter. If the car is "off" you are looking at the 12V battery voltage (measure at the boost terminal in the underhood fusebox and use the bolt on the firewall above it for ground or -ve). It should be between 11.5 and 13.5V. When the car is "on" (ready or ig. on) you will be measuring the charger voltage or system voltage. It should be 13.8V constantly. It -may- drop about 0.1V when you turn the headlamps on. That is normal.

There is a ground connection from the battery to the chassis. The system uses that as a power conductor. It's in the right rear of the car. There have been reported cases of the ground connection becoming loose or corroded. It's easy to check. Remove the rear hatch floor (lid for the under hatch floor storage area), then the right rear corner floor piece. The battery is under that. You can see the ground connection on the "rear" of the battery, from the -ve post to the chassis.

The power from the 12V battery goes through a 100 Amp fuse to the front of the car into the fuse box on the drivers side (left). It is at the "boost terminal", from where it is split into the rest of the systems that need it. Be careful, it's always live.

If you remove either terminal connection from the 12V battery you will have to reprogram the radio and the power window safety system (roll window 1/2 way down then all the way up as per the owners manual). DO NOT remove either terminal when the car is on!

 

Has anyone found any solutions to the Prius headlamp problems? I see this issue is ages old or as long as Prius have been coming out. I am experiencing this problem too and do not want to pay the Toyota prices being quoted. I have another appointment today with the dealer and I am sure they will say what they always say and want to charge $400 each light plus service charges. The problem is more than this. I am very frustrated and am ready to start a real negative campaign. This is just not ok. I paid extended warranty and still I get no help. Any other frustrated owners out there?

 

I'm also experiencing the same problems with my headlamps, has been the passenger side lights for several months and my driver side also began going out recently so i finally took it into the dealer today. They quoted me 1650.00 to replace two ECU's (one for each light). After I told the guy he was nuts and I wasn't paying that much for headlights he said that they've had the compliant before and advised me to inform Toyota via the customer care. I also checked out Priuschat.com and there seem to be several people with this problem,just as the guy said. Everyone experiencing this problem NEEDS TO FILE A COMPLAINT TO MAKE TOYOTA ISSUE A RECALL!