Replaced both headlight bulbs about a year ago. All was working fine. No flickering. HI/LO working. Had a rain storm with tons of water on Tuesday. Got drowned by another vehicle passing on my drivers side on the way home. This SUV threw so much water across the hood, I had no vision for about 5 seconds. Thought things looked darker than normal the rest of the drive home, but didn't notice if the light was out upon parking in the garage, The next day, the driver side headlight is out. Checked the light and there is moisture inside. Tried replacing headlight bulb, still not working. Checked fuses, HI/LO, all ok. Thinking ballast got wet and fried. Hubby wants to get rid of car, as he wants a Camry. I want to keep it, as I don't see the sense in getting rid of a car that is working, if it just needs a new headlight assembly. Should I replace entire assembly, or could it be a relay I am overlooking? Of note, also, is the inverter coolant pump was recently replaced by a dealership. Same one that wants us to trade in this car. Any chance they messed something up when changing the pump? While changing the pump is pretty straight forward, it failed when I was out of town. Hence the dealership work. Pulled the light today. It had about 3/4 cup of water in the bottom of it. Have a new one on order. Hopefully, after install, it will work well and I will be back on the road.
Did the replacement of the headlight assembly solve your problem? I am also desperate to find the retainer clip for the headlight bulb. If you still have the old one, I would be very happy to purchase it from you.
So far, still dealing with it. Ordered a new headlight from Go-parts.com. Took them a week to get it to me. Opened today to find a headlight assembly, with no ballast. Since my ballast got waterlogged, that doesn't help me. Of course, they are closed over the weekend. You might try Griffithmotorsparts.com. They are a dealership out of the Dalles, OR. They seem to have or be able to order the odd things none of the other dealerships will bother with.
We too have a 2007 Prius with 167K miles on it and have experienced headlight issues over the years. Each time they would begin to go out intermittently and after turning them on and off would work again for a time. Here is our history with the issue. Replaced ECU on both headlights under warranty 8/2009. This took care of the issue for many years. I had to replace both ballasts and bulbs Dec. 2014. Did this myself after watching YouTube videos. Ordered OEM parts from eBay. I replaced passenger side ballast (ECU) and new bulb June 27, 2017 after having the intermittent issue return on the passenger side only. Got OEM parts marked Toyota through Amazon. This didn't fix it and we have continued having it go out intermittently. Since it was intermittent and on the passenger side I lived with it. Driver's side headlight went out completely and wouldn't turn back on a couple of weeks ago. We have a community college that has an auto repair program and I was able to get it into their electrical class. They changed the fuse back to the 15 amp. They replaced both ballasts (ECU) with Toyota dealer parts on Nov. 29, 2017. Found out they were still not working, but having the intermittent issue that evening. Yesterday they replaced driver's side headlight with Toyota Bulb but we are still having the intermittent issue. When I call Toyota service, one dealer claims that they have never seen this issue and the other one knows it is an issue but would do what we have already done. Has anyone had this issue and not been able to get it corrected through these measures? This is getting old and costly as well as time consuming. Any suggestions would be greatly appreciated. Other than this, the car has been wonderful and we enjoy driving it.
Following! 2007 Prius at 154k now and right one is acting the same! Need to get these HID fixed on a tight budget as I drive a ton at night for work. iPhone ?
If one side works and the other doesn't, I would first try switching the bulbs from one side to the other, to try to determine whether it is the bulb that is at fault or something else (most likely the ballast). I think many people have found that bulbs that were advertised as OEM were not always such. Bad bulbs seem to be a more frequent problem than ballast needing to be replaced. You can read about my experience at HID headlight (cover too tight) help? | PriusChat. 9 months later things are still good with the bulbs I bought.
Glad yours is fixed. As we mentioned above we've replaced ballasts and bulbs with OEM a few times and this last time with parts directly from a Toyota dealer. Driver's side is still not working and goes off at least once every time we drive it. Now we turn them off during the day and only use at night but always have the fog lamps on so that something shows up as we are not certain when we have the driver's side on and when it is off. Hoping someone else has had this issue and might have some suggestions.
I have to admit, I am still constantly checking the reflection of our headlights and fog lights in the car ahead's bumper when we pull up behind someone, because I've become a little paranoid about losing them again. After replacing both headlight bulbs in March, a couple of months later I had to replace one of the fog light bulbs and then the other one a few months after that. I was advised to replace both headlight bulbs at the same time, even though only the driver's side was failing. When the first fog light went out, I decided to replace only that one because the lens on that side was cracked, and I thought maybe moisture had gotten into the assembly and caused it to fail, but I guess in my case, that was not the cause, since the other one failed a few months later. I wonder if moisture intrusion might be causing the problems with your car's headlight bulbs.