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Subject:Re: headlights on with ignition on!
From:David Marshall
Date:Fri, 14 Dec 2007 15:16:59 -0800

In Canada, starting October 1, 1989 Day Time Running lights were mandatory
on all new vehicles sold.

Normally there is no relays in your
light circuit so this would rule out a bad relay.

Canadian and
Scandinavian T3s used a relay for DTRLs.  The DTRLs were the low beam
circuit.  It is documented in the Bentley manual on how it was
done.  Pulling the relay results in no DTRLs.

For
those who want to add the circuit, it is quite neat.  A simple
30-85-86-87 relay is used with the following pinouts:

30   12V constant
85   12V switched
86   High beam circuit
87   Low beam circuit

Basically for a relay to turn on, you need 12V across 85 and
86.  So with the high beam circuit off - there is some resistance in
the bulb filament but not enough to prevent the relay from
"seeing" ground, so with the high beams off and the ignition
turned on, the relay triggers.  As soon as the user goes from low
beam to high beam the high beam circuit goes to 12V and the difference
across the relay is now zero and the relay goes off, thus preventing both
the low and high beams to be on at the same time.

David
Marshall

http://www.hasenwerk.ca
http://www.fastforward.ca

Box 4153, Quesnel BC, Canada V2J
3J2

On Fri, December 14, 2007 13:29, robert feller wrote:
> Is there a common hack out there that I'm not familar with with
someone
> can
> wire the headlights to be on any time the
ignition is on? Or could this be
> a
> bad relay? I've
seen high beems on when they shouldn't be with my Saabs.
>
> Again, got a 96 syncro that is newer to me and just noticed that
the
> headlights are always on with the ignition! May want to get
this back to
> normal when I do the relay/bulb upgrade in a couple
of weeks.
>
> --
> Shawn Feller
> Ohio
> www.carboncow.com
>