I have a very frustrating problem with my 06 Mazda 5. The car now has 83,000 miles on it, and it is on its 3 set of low beam bulbs. These bulbs are the stock replacement, and are not touched when installing. I have never had any other bulbs burn out, just the low beams. They useally go within a day of each other or so, but last night both at the same time. I limped home on the driving lights. I installed new bulbs and I should be good for another 11 months or so.

I noticed last night, that when the you are on High Beam, both the low beam bulb and the High beam bulb are on. Is this normal?

The driving lights were installed at the dealer before I purchased it Brand New at my request. Could they have wired something wrong? It is a plug and play system from what the dealer told me at the time!

 

I don't have any experience with this sort of thing on Mazdas but I had a Mondeo that kept blowing bulbs. It was caused, I believe, by the voltage regulator on the alternator causing power surges as when the alternator finally gave up (after 110k miles) and was replaced with a reconditioned unit it stopped blowing bulbs. FYI it always blew the dipped beam bulbs but I expect this was because they were on much more of the time than the main beam. It never blew sidelight bulbs FWIW.

So you may want to get the alternator's output checked to make sure it's not the causof them blowing.

 

That was of the first things that I had tested. I talked with the dealer the other day, and he stated that Sylvania bulbs do not last in a Mazda. I thought it sounded like a little BS.

 

Sylvania Silverstars have notorious short bulb life. I had one go out after 3 days in my Mazda6.

 

I have an 04 Mazda 3 and have never had a problem with the headlights till last night. When both of my low beams died at the same time!!! My brights work and I turned my low beams off and on several times to try to get them to work and nothing happened. I am frustrated! I stopped at an auto store and he said my fuse was still good. So I am wondering is there a relay I need to have checked out or a switch, or should I just have the bulbs replaced?! OH and I want to apologize to everyone I blinded with my high beams all the way home last night. During my hour drive home!

 

Lamps that are marketed as having whiter light basically cheat to get that whiter light. To make whiter light, the temperature has to go up - and to get that temperature up, the lamp is designed to run at slightly lower voltage. I won't get into the gases used to help with this in incandescent lamps - the principle is still the same.

If your alternator is truly putting out acceptable voltage, then I think your issue is likely due to high heat. Also - the projector enclosures tend to dissipate heat slower than a freeform lens, so I'm betting the filament is just getting too dang hot.

Put some LongLife lamps in (often LL at the end of the part number). These are designed to run at a slightly higher voltage, thus running cooler, and lasting longer - unfortunately they're not as pretty.

 

One solution to intermittent or permanent headlight failure can be found on the post by SEVARGMT on 9-29-2010.

It seems to lie in corrosion of the wiring system connectors in the PJB, a specific wire connection junction box located under the passenger side glove compartment box.

It seems possible to repair the corroded pin connector but it is probably best to have the dealer replace the entire PJB to avoid repeats of this problem, as it is a dangerous situation when headlights go out at night, like mine did.

Brilliant problem solving by SEVARGMT and DJS2571. They also developed a convincing theory of what causes this problem: the air conditioning line located above this box creates condensation, which then drips down on the wire connectors and causes them to corrode, causing an electrical fault. They suggest a plastic drip sheet to avoid future corrosion.

Wouldn't it be great if Mazda assigned an engineer to read the forums for problems with their cars and prepare posts with solutions? It is plainly obvious that a problem is very common when you look at the number of "views" listed for certain topics, such the headlights (many thousands of owners have headlight failure problems). Mazda should have issued a bulletin or a recall since the corroding PJB is clearly a safety problem. This looks like a design/engineering flaw. Every electrician and plumber knows to never put moisture sources above electrical boxes. Shame on them.

 

Going to resurrect this thread.

This is constantly happening to me, but back and forth. I have a 06 Mazda 5, about 75k. Low-beams seem to burn out, Left, Right, Left, Right...about one every 2-3 months. That seems really ridiculous, given our other car - a 2000 Ols Alero with about 120k has never had a low-beam burn out. :/

Anyone had success with the corrosion fix mentioned by @skidder! ?

Also - any advice on best bulbs? Maybe I just get bargain crap ones or something...
Thanks.

 

I fixed my problem for good a while ago. I just converted the low beams to HID for under $90 and have not had a problem ever since. I bought a US sold kit, and installed it in under an hour. My lighting is awesome now, and I don't have to worry about bulbs any more. I installed the optional 40 amp relay circut that the company sells for imports with wimpy headlight circuts, which isolated the HID lights from the stock wiring. It was plug and play, and I kick myself in the **** for not doing this sooner, since I am now rolling 145,000 miles.

 

I have a 2011 CX-7 w/130,000 mi and I am currently sitting at the dealership getting the 4th bulb installed on the drivers side. I have had the same issues that I read in this thread. One light will go out then within 1 - 2 weeks the other will go out. This has happenned three times since I bought it new 2011. There has to be an issue but the dealers says no.