Headlight problem

Well, I'm in the same boat as many of the folks on this thread. 2006 Prius, RH headlamp will stop working and turning the headlights off then on fixes it for the time being. The LH has had the problem once but the RH side many times. Less than 50k miles but we have an extended warranty.

We're calling the dealer this week and will report back on the outcome. I just wanted to add myself to the list of people having the exact same issue.

 

They will try to say bulbs are a maintenance item and not a warranty factory defect issue.

But if they run an analysis and confirm its the ballast etc they will fix the whole thing but if you authorize an analysis and its only the bulbs, you get to pay for the analysis.... funny how that works.......

 

For what it's worth, it looks like I was hoodwinked into buying a used Prius with two bad headlights. A certified used Prius from a dealership, no less. One died the day I bought the damn thing, the other started acting up a week later.

The dealership is giving me the runaround, offered to split the bill with me, but frankly i'm livid. To have to shell out $250 for a headlight before making my first payment on the car reeks of BS.

The moral of the story, I guess, is do your test driving at night.

Grr.

 

Let him give you the split and then do it yourself for 44.00 for both.

 

I have been having the problem where a light will go out but then start working again if the headlights are turned off and then on again. Rather than making me read through 72 pages, is this the symptom of a headlight bulb going bad? I hate to dig into the system if it's just the bulb. Car has almost 70k on it. My left bulb has done this to me a couple of times, it just happened with the right.

 

Your chance of it being a bulb I would say is in the high 90's.
Order ebay bulbs for 44.00 a pair and go for it.

You didn't say what year you have but I use 4300K d4R for my 2006
4300K HID 35W Xenon OEM Toyota Prius 06 07-09 Bulbs D4R - eBay (item 270648695747 end time Jan-10-11 13:34:15 PST)
Here is my how to thread plus a couple more.
http://priuschat.com/forums/gen-ii-...7938-my-hid-bulb-replacement-my-06-prius.html

http://priuschat.com/forums/toyota-prius-service-bulletins-tsbs/42999-headlight-replacement.html
http://priuschat.com/forums/knowled...38842-how-change-headlamp-headlight-bulb.html

 

For those wondering what they may be doing to cause the light to go out, I have noticed that the problem occurs during acceleration. If you accelerate like Grandma, the light will stay on but I tend to accelerate a bit quicker, and if you do too, then watch the headlight go out.

This leads me to believe that the issue is with the electrical system, and not the bulb itself. Turning the lights off and back on returns the bulb to operation....until I stomp on the gas at the next green light.

 

That would not explain why a new bulb permanently fixes the problem for another 80K miles?

As bulbs go bad, internal resistance climbs causing more heat and less amperage to pass to make the arc.

Turning the light off and back on initiates another extremely high voltage burst to restart the bulb but then as the voltage drops back to normal, the impurities or whatever causes the high resistance in the bulb causes the problem again since the lower voltage is not enough to make the trip and keep all the material inside the bulb vaporized.

Replace your bulb and I'm sure your electrical problem will be fixed!

 

I think it does explain it as an electrical problem...if I accelerate smoothly, I can get the light to stay on for over an hour long drive home from work. It's the high acceleration that causes the bulb to turn off, meaning that I'm offering less electricity to the bulb during the acceleration. You can see this when you accelerate harder as a slight dimming of the bulb as electrical power is delivered to the electric motors. If done smoothly and with light acceleration, the lights don’t dim as the drain of electricity to the drive motors is less. It’s this dimming of the lights, or the reduction of power that occurs when large amounts of electrical power is redirected to the electric motors that causes these bulbs to fail. If the electricity to the lights was controlled properly by the electrical system, this would prevent the bulb from starving electricity and turning off.

 

You also point out an issue with the bulb itself in that the bulbs do go bad over time, and this too can be caused by the unstable supply of electricity these bulbs receive during normal use. I would say again, that proper control of the electrical system these bulbs are connected to would extend the life of the bulb, and this would no longer be a problem. Besides, 80,000 miles for a light bulb is simply ludicrous for how much they cost, even if you’re doing the repair yourself.

 

For those that are keeping track, I went to my dealer today to have the recall work done and while the car was in there I complained about my headlights and them randomly working. After giving me the run around about how that is "normal" behaviour when the bulbs are going and that I was outside of the bulb warranty period, I did see the technician explicitly type "Customer states that headlights work intermittently." Then he told me that he would get back to me but if they ended up replacing the bulb that it would take 4 hours on top of the two hours to do the recall work.

One hour and forty-five minutes later, I get the car back and am informed that both headlight bulbs were replaced at no cost. So, while I could have gone without the run around, I am happy that ultimately the right thing was done because I had prepared myself for having to do battle over this.

I think that the comments on this thread referring to the need to use words like "intermittent" and "flickering" may have some merit.

Good luck on your headlight endeavors.

John

 

I believe the inverter supplied 12V to all the accessories "up to 1400Watts or so" and I could be mistaken but I think the bulbs are included in that. The Ballast then takes the 12V and converts it to the much higher voltages to fire the bulb and then drops it to around 70Volts or so to maintain the burn.
If you are having those symptoms I would think you would also see the bulbs in your car dim as you accelerate.
Remember the Prius does not run off a a belt driven alternator that gets more juice when the engine revs or has any relation at all. The only common denominator between the two is the main traction battery.... and that would have to be basically dead to show a fluxuation of 35W X 2 worth of car lights.

The engine itself runs off the high voltage of 206Volts and even higher internally which has no relation to the inverter.

I would call the prius service guy at your dealer and pick his brain and tell him your symptoms and see if he can piece any relation to the bulbs.

So far based on my fragmented knowledge base of the total electrical system, I can't see how accelerating the car would take away or add to the voltage of the 12V supplied from the inverter to the ballast that power the bulbs.

Maybe he can shed some more light!... Sorry a small pun!

 

Welcome to the forum BigJohn!
Thats encouraging and it never hurts to see what they will do. I hear stories like that but it seems only when they are sparse and far and few between do they honor such a good will gesture of doing what is right.

I think they are afraid of setting a precedence and having a run of not only those folks with legitimate claims but those who simply know the life of their bulb is running out and want a fresh bulb!

 

I have similiar problems with the RH passenger headlight. I even replaced the bulb but same issue. I think in my case something else is not working.

 

its quite rare that its not the bulb... so much so that its by far the best gamble just to replace it.
But if you take it to the dealer, you might want to put the bad one back in and keep your new one as a backup.
If they find its the Control unit or ballast they will replace it anyway.

If you go back and look at the last 3 - 4 years, I only remember two or three that have claims of replacing the bulb and it not working.

Keep in mind when I replaced mine, one of the 4 bulbs I bought had the same symptoms within 2 weeks indicating I got a bad bulb... I simple put one of my originals that hadn't gone bad in its place and it continued to run till now.....

In other words, there is a percent of bad bulbs that are released... seems QA is pretty poor on them.

If you care to go through the trouble, its always recommended to switch bulbs from right to left to see if your symptoms follow... if so, its the bulb for sure.... if it continues on the same side, then you have other issues.

 

I googled the life span of these HID D4R bulbs and got anywhere from 1500 - 2500 hours. This sounds about right to me. I have also had my bulbs go out and had to reset them to turn them back on. 1st time it happened was the drivers side, I was under warrenty and took it back to the dealership, they replaced the bulb and then a few months later the other side went. Out of warrenty I bought and replaced both at the same time. Now again both are going out. So now I'm just trying to find a cheap pair on ebay right now, before they totally go out when i need them.

 

These are the ones I used and I"ve gotten about 80K out of the 3 that remained good.... Just starting to have issues again, but don't know yet if its the original OEM or one of the ebay... I"ve got about 130K on that rig now... so either way, I got good life.... 80K is good, 130K is really good!
I've seen them for cheaper but 22.00 a piece is not bad and I trust these, people have had issues with some of the others.
I requested the 4300K D4R's for my 2006.
I suppose the D4S is supposed to be the same thing without the ceramic band at the base and therefore release more light but It could be light in the wrong place since the reflector is custom made for the D4R's.

http://cgi.ebay.com/ebaymotors/NEW-...r_Truck_Parts_Accessories&hash=item518af0e884

 

I have a 2007 and have the same problem. Stared with one headlight and now both will go out. Also tried web site suggested to lodge a complaint but can't find out how to do it????

 

This often happens right after starting the car, so heat isn't the problem

 

Sorry if I didn't explain well.

Heat is not the issue.. resistance is.

If you examine a bad bulb verses a good bulb you will see lots of crystallized material that never gets to vaporize well.

Think of it like a campfire that has impure fuel that won't burn unless it has tremendous heat to get it started.
I'm sure you've built a fire just to have it go out again.... that you get burning but there just isn't quite enough kindling to keep the fire burning for long unless you pour a second dose of gasoline on the fire or reintroduce the propane torch!

That second burst is a much much higher voltage and its being sent into a bulb thats already hot "meaning its easier to fire the second time than the first".

As the bulb continues to degrade over days or weeks the material inside continues to get harder and harder to keep burning "vaporized" at the lower voltages so the high voltage burst "jump starts" from turning it off and back on become needed more and more frequent.

If first did mine in April of 2008 and here are some instructions I created.
I just had one of my ebay bulbs go bad again... looks like it lasted 80K.... not bad.