About three weeks ago, driver's side dipped beam bulb fails.  Buy a new pair and replace it.  Less than a week later, the passenger side goes.

 

Today, one of the brake lights has failed. Just a weird coincidence or time to check for faults?

Psychiatrist's rule of three: once is a concern, twice is a problem, thrice is a pattern.

I'm always intrigued as to how my cars need new bulbs to pass an MoT when the lights were working when the car got left!

Psychiatrist's rule of three: once is a concern, twice is a problem, thrice is a pattern.

 

I'll monitor it.  Obviously I've no idea when the bulbs were changed prior to me buying it, but it just seems odd for three to fail all within a month.  Could be a temperature change thing though?

if it's not a bulb it will be a wiper blade for the mot.

The paint on the indicator bulbs over time cracks and flakes off leaving a clear/ partially clear bulb which give off a white or less orange light so although working they aren't to spec.

Hazza, I've had two number plate led's go within 2-3 days of each other and then a hid headlight less than a week later, I'm putting it down to the weather.

The paint on the indicator bulbs over time cracks and flakes off leaving a clear/ partially clear bulb which give off a white or less orange light so although working they aren't to spec.

Hazza, I've had two number plate led's go within 2-3 days of each other and then a hid headlight less than a week later, I'm putting it down to the weather.

 

Well the bulbs are old and we've had the weather recently where it's been 15C at 7AM one day, then ~0C 48 hours later.

And like clockwork, the other brake light has gone out today...

Maxidot will scroll through ALL bulbs that are out.

I connected a new trailer to my Yeti the other day and Maxidot showed a hissy-fit as it wasn't connected properly at the plug and it thought all the trailer bulbs were blown.

Took quite a while scrolling through the list on the display...

I agree that two is a conincidence (although I've had both headlight bulbs go within weeks of each other - they were last replaced as a pair, so no real surprise), but any more in a short space of time and that suggests there might be a problem somewhere.

Check voltage across the battery with engine running. Failing voltage regulators sometimes put out too high a voltage, which is a real bulb killer when combined with cold.

Psychiatrist's rule of three: once is a concern, twice is a problem, thrice is a pattern. :)

Soldier's rule of three: Once is happenstance, twice is coincidence, third time is enemy action!!

 

Not sure who teh enemy would be in this case - Gremlins? Corrosion?

According to the fitters at work who repair our coaches, the enemy would be driver error................

 

Mike

Aren't any of them proper mechanics, then? :p :D

 

My in-law is a fitter for Porsche. I love winding him up!!

Well so far, none of the bulbs have blown twice. Every time it's a different, old bulb that has failed, so it could still just be age.  My car is non maxidot, so it's just an archaic check with all the lights on and walking around to see which has failed.  That or plug in VCDS, but I don't have my laptop in the car.

They are 21/4 not 21/5 watt, and you might be only to get these from the dealers. I haven't found anywhere local except the dealers to get replacements.

 

Halfords do a selection of P21/4W bulbs :)

 

http://www.halfords.com/motoring/bulbs-blades-batteries/car-bulbs/halfords-566-p21-4w-car-bulb-x-1

http://www.halfords.com/motoring/bulbs-blades-batteries/car-bulbs/ge-566-p21-4w-car-bulb-x-1

http://www.halfords.com/motoring/bulbs-blades-batteries/car-bulbs/bosch-566-p21-4w-car-bulbs-x-2

It's actually my reg plate bulb that's gone ha. Serves me right for jumping to conclusions.

Checking vcds, I do have a couple of codes. One regarding alarm horn and the other exam power relay. That's due to my battery failing recently though.

Edited 13 January, 20179 yr by planehazza

I believe the theory is that as the bulb blows it causes a surge as the resistance temporarily increases. Once the resistance dissipates quickly that energy then hits the other bulbs.

It is just a small surge but enough to cause damage. Then at this time of year with temperature fluctuations it causes higher stress on the original bulbs. Hence they fail soon after the first.

I usually replace in pairs so I know that all are of an equal age and brightness