Re: Driving/Fog Lights

[PDQSHIP@aol.com]

In a message dated 95-09-21 20:44:52 EDT, you write:

>
>I added some individual relays to improve the voltage reaching the headlamps
>on my 1986
>5000CS Turbo when I added some high wattage 9004 bulbs.  My nice new high
>wattage bulbs
>started burning out only after 3 -6 months of use so I went back to the
>standard bulbs wattage
>55/65W. Even with the stock bulbs I still was replacing the bulbs every
12-18
>months.
>
>Most bulbs burn out when they are first turned on (cold) due to low bulb
>resistance and the
>fact that the inrush current is something like 5-10 times the normal
>operating current. I have
>measured this using a current probe and an oscilloscope. This is also true
>for most household
>light bulbs.
>
>Previously I had gone several years without replacing any bulbs. I theorized
>that the shorter
>bulb life was caused by 1. (lousy bulb manufacturer) or 2. The relays I
added
>had lowered the 
>voltage source resistance enough that the inrush current was being
increased.
>Eventually
> this burned out  the bulb sooner than when I had the stock wiring with all
>of the added resistance 
>from the fuse box through the headlamp switch and out to the lights.
>
>Any one else had this sort of problem with lights burning out? Just one
nerds
>opinion.
>
>One of my PIAA 959  (85W) bulbs burned out after around 2 years of use.
>
>Scott M.
>
>

I have run relays in just about all aux liting in my toys for years
(including the 9 on my pro rally scirocco) and will say that this theory of
current just isn't true, infact, relays tend to null the effects of "spikes"
to the bulbs during use.......  My guess is that you have a leak in your lens
assbly, it could be small, but that;s all it takes......  You may want to ck
the integrity of the bulb o-rings and the lens assbly itself for cracks
either in the lens or where it joins the backing.......  If you see any water
in the lens during off time or on time, you have a leak......  I'm assuming
you know that, but the life of the bulb goes down if you don't have a good
heat/vacuum seal......  I ran 10guage wire to my hella conversions X 2 hibeam
relays in my Ford Crown Vic tow vehicle (55/100 hi/lo and 100w hi) for 5years
with no burnout of the bulb.....  Relays are a good thing, don't change that,
maybe the bulb manufacturer, could be, but after running 55/100 in my 5ktq, I
can tell you that most likely you have a moisture prollum that blows the
bulbs......  I will reiterate however, my feelings on hi watt 9004's.....  If
you take the argument that the US lens patterns suck, and they do, putting in
hi wattage bulbs just exponentially increases the garbage out......


Scott