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Re: Keeping low-beams on with the highs

-----Original Message-----
From: Rob Winchell <rbw@avs.com>
To: Quattro <quattro@coimbra.ans.net>
Date: Thursday, June 25, 1998 1:01 PM
Subject: Keeping low-beams on with the highs

>Q -
>Yes I know this is a FAQ.
>How can I wire my lights so that the low-beams stay on with the high-beams
>(like during that split second when you switch between them). I'm talking
>a single bulb (9004 or 9007) setup.
>Rob Winchell
>91 200Q
>87 4kCS

Hi Rob;

    It is relatively easy to wire up a system to run both high and low beams
together, but you are likely to experience two problems:
    1. The bulbs will burn out in short order from the heat generated by the
two filaments on at once.
    2. The connectors on 9004 bulbs have a small surface area. The ground
pin will fry if it carries the current from the high and low beams
simultaneously for any length of time.

    I recently had a problem on my '91 200q which resulted in a 7V current
on the high beams when the low beams were on. The ground connector on the
bulbs fried even though full voltage wasn't on the high beams.
    I installed a relay system triggered off the stock wiring circuit and
the same problem activated both beams at once. The 55/100w bulbs lasted 30
seconds. The replacement stock 55/65w bulbs lasted about one hour. At this
point I realized I had a problem and tracked it down ( and got my low speed
rad fan circuit working at the same time, but that story is in the archives
    BTW, having both beams on is not much improvement on the stock lights,
although it does give you the lighting a good low beam system should provide


Fred Munro
'91 200q  255k km