Both headlights have failed at the same time - Is it just the bulbs or could it be something else?

[j***@hotmail.com]

I have a ford focus estate 02 reg which I bought 2 years ago and has
been problem free apart from a number of light bulbs blowing. Now both
headlights have gone at the same time , is this just coincidence or
could it be something else?
I haven't taken them out yet to examine, can you tell if a headlight
bulb has blown just by looking at it?

[Adrian]

Post by j***@hotmail.com
I have a ford focus estate 02 reg which I bought 2 years ago and has
been problem free apart from a number of light bulbs blowing. Now both
headlights have gone at the same time , is this just coincidence or
could it be something else?

I had both dip bulbs go simultaneously on the XM - got into it, turned
the lights on, they went bright-dim-bright-out. My immediate reaction was
that it couldn't possibly be the bulbs, must be something else. So I
replaced all the relays, cleaned the connections, etc. etc.

Then I looked at the bulbs. Both dead. They weren't even the same age or
brand - but both were a several of years old. The replacements were still
fine when I sold the car 18mo later.

Just one of those coincidences.

Post by j***@hotmail.com
I haven't taken them out yet to examine, can you tell if a headlight
bulb has blown just by looking at it?

Usually, yes. But if you want to be REALLY sure, just spend two minutes
with a multimeter checking you've got power to the connector.

[Chris Whelan]

Post by j***@hotmail.com
I have a ford focus estate 02 reg which I bought 2 years ago and has
been problem free apart from a number of light bulbs blowing. Now both
headlights have gone at the same time , is this just coincidence or
could it be something else?

Maybe, and maybe ;-)

You could test for voltage at the bulbholder, but access is tricky enough
that you might want to replace the bulbs at that point anyway.

Post by j***@hotmail.com
I haven't taken them out yet to examine, can you tell if a headlight
bulb has blown just by looking at it?

No, visual inspection is unlikely to be a reliable test.

FWIW, I've had a '99 Focus from new. It's done 92K miles. The only bulb I've
needed to replace has been one brakelight, although I did uprate the
headlight bulbs when it was about a year old.

Is it always the headlight bulbs that blow? If so, are you absolutely sure
that you are not touching the glass at all during installation? Are you
buying good quality ones?

Chris

[j***@hotmail.com]

Post by Chris Whelan
Is it always the headlight bulbs that blow? If so, are you absolutely sure
that you are not touching the glass at all during installation? Are you
buying good quality ones?
Chris

Chris, no it's not always the headlight bulb that's blown.

I probably have touched the glass suring installation , is that a bad
thing? As long as it worked when fitted I was happy!

I Just bought whatever the local parts shop gave me, is there a
particular brand/s you recommend or ones I should avoid?

Thanks, John

[Adrian]

Post by j***@hotmail.com
I probably have touched the glass suring installation , is that a bad
thing? As long as it worked when fitted I was happy!

Yes, very bad on headlight bulbs. The oils from your fingers causes
localised hotspots which burn the bulbs out quickly.

Non-headlight bulbs, less of an issue, but still better not to.

[Chris Whelan]

Post by j***@hotmail.com

Post by Chris Whelan
Is it always the headlight bulbs that blow? If so, are you absolutely
sure that you are not touching the glass at all during installation? Are
you buying good quality ones?
Chris

Chris, no it's not always the headlight bulb that's blown.
I probably have touched the glass suring installation , is that a bad
thing? As long as it worked when fitted I was happy!

A Very Bad Thing indeed!

Halogen lamps run at very high temperatures, so the transferred oils from
your skin cause local hot spots and early failure. It's difficult to avoid
where access is tricky; if it does happen, clean the glass carefully with
methylated spirits before switching it on.

Post by j***@hotmail.com
I Just bought whatever the local parts shop gave me, is there a
particular brand/s you recommend or ones I should avoid?
Thanks, John

There are lots of poor quality bulbs around. Perhaps it would be worth
trying a dealer, or Halfords (spit) for your next ones?

As a technical aside, most cars (and all Fords) made since about 2000 use
silver technology batteries. These require a slightly higher charging
voltage, and this in part accounts for more frequent bulb replacement.

Chris

[Adrian]

Post by Chris Whelan

Post by j***@hotmail.com
I probably have touched the glass suring installation , is that a bad
thing? As long as it worked when fitted I was happy!

A Very Bad Thing indeed!
Halogen lamps run at very high temperatures, so the transferred oils
from your skin cause local hot spots and early failure. It's difficult
to avoid where access is tricky

It's easy. Latex/nitrile "rubber" gloves. Not only do they save the bulb
from fingerprints, but they save your hand from the many scrapes and
scratches that are inevitable with well buried bulb access.

Fiver for a box of a hundred, keep 'em in the boot.