Re: Weird,weird lighting problem!

[Don Hoefer <hoefer@jaxom.eng.pko.dec.com>]

Rob rightly wonders:

> Problem- dash lights do not light. Computer and
> AC lights are dimmed with headlights on, but I am flying blind. Weird
> twist: This Audi answer to Saab's "black panel" can be defeated. If I
> switch on the headlights before starting the motor, the lights work.

I'm just taking a shot in the dark here (ha ha, sorry) but dimmers (and
any other connections) are very sensitive to voltage variations.  Especially
old, worn, or dirty dimmers.  While the voltage available should be greater
when the engine is on, there may be a greater load on that particular
circuit while the engine is running.  This may reduce the voltage enough
that the bulbs do not light.  Not all of the lights may be on the dimmer.
Perhaps the computer and AC lights are not, which is why they are not
affected.  Does playing with the dimmer or pounding on the dash make any
difference?

In my house I have a dimmer on a chandelier and it is on the same circuit
as a window air conditioner.  Unless the dimmer is turned all the way up,
the lights will go on and off as the window AC compressor cycles.

Don Hoefer
'82 Coupe