Headlight bulb life

[Huw Powell]

> I finally got my H4 euro's installed on my 4kq not too long ago, and
> I can finally see where I'm going.  They are a huge improvement.  The
> only thing is that the bulbs are only lasting about a month or so.

There is definitely something wrong there.  I routinely get about a year
  of regular use from 80/100 H4's in my coupe and the 90Q.  Usually the
low beam filament dies.

I would suspect one of the two theories already suggested - lots of
vibration (are the lenses securely mounted?  do you live down a five
mile washboard dirt road?) or voltage issues (how does the voltage at
your alt output/battery look?).  Also I would add temperature shock -
perhaps if it is *very* cold turning them on could be an issue, or if
somehow cold ice/water can get to the bulb through the housing.

> The way these are wired, there is heavy gauge wire from the alt
> (fused) to a separate relay for each high & low beam triggered by the
> old wiring from the switch.  They are grounded with good size wire
> right to the core support.

That all sounds good.

--
Huw Powell

http://www.humanspeakers.com/audi

http://www.humanthoughts.org/