Light bulbs keep blowing

The same bulbs seem to blow rather more often than I am used to. Voltage regulator, maybe? We've been through 3 headlight bulbs and several sidelight bulbs in the last 3 years. Bugger to fit too, in a Punto.

Reply to
GB
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You will need a reasonably accurate multimeter to check the voltage, but it's pretty unlikely that's the cause. Why would it only affect the front lights?

Have the failures mostly been on the same side? If so, disconnect and clean all connections; intermittent connection can pulse the lamp on and off quicker than can be seen, thermally shocking it to early failure.

Is it the replacements that have subsequently failed? If so, are they from a reputable source? Cheap lamps are cheap for a reason!

WRT the headlight ones, it's easy to accidentally touch the glass when fitting them, especially if they are awkward, which will lead to early failure.

In 10 years, I had one bulb failure (with the same car), so your situation does seem unusual.

Chris

Reply to
Chris Whelan

Probably cheapo bulbs. Try putting a meter across the lighting circuit. You shouldn't get more than 14 Volts

Reply to
John

Also, check for firmness of fitting of the light unit to the bodywork. Slight looseness of the fitting can cause vibrations which give the symptoms you describe. It does on our coaches, anyway.

Reply to
John Williamson

A bad earth is a common cause.

Reply to
Dave Baker

Had a similar problem with the old relay, never did find the cause but i was advised to leave the lights off when starting up which did help.

When i multimetered it out it showed a drop to 11 volts when starting and a peak of 17 volts once started before dropping back to 14.5 volts All over a 3 second window

Reply to
steve robinson

Thanks to everyone. I'll check the voltages first, then move on from there.

Reply to
GB

I'd say the most common cause.

Reply to
sweller

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