From: mlschmidt@sprintmail.com
Sent: Wednesday, May 29, 2002 9:49 PM
To: 928
Subject: [928] Dim instrument lighting

Dim instrument lighting seems to be pretty common on 928s. There are three
triangular shaped plastic pieces on the bottom of the gauge housing. These
have a chrome-like finish on them, and are what transfers the light from
the bulb to illuminate the gauges, in a fiber-optic sort of way. One of the
reasons that the instrument lighting is dim on many cars is because the
chrome-like finish on the plastic pieces has deteriorated over time. Mine
were more of a dull primer gray color than chrome. The chromed plastic
pieces aren't available separately, so you'd have to buy a whole new gauge
housing to really correct the problem. I experimented with a couple of
different chrome spray paints, but those didn't look any better than the
messed up original coating that I had before I started. The side of the
paint surface that actually contacts the clear plastic is what's really the
important surface, the same as the reflective coating on the back of a
mirror. With the regular chrome spray paints I tried, that surface against
the clear plastic was just gray.

Today I found a solution though. At a local hobby shop I came across Alcad2
chrome paint. This is not like any of that other chrome paint you've
probably seen. Don't let the way it looks in the bottle fool you. It looks
amazingly like chrome plating when sprayed on. The instructions state that
you should use a gloss black paint as a sort of primer under it to get the
proper chrome finish. Since the reflective surface on the three plastic
gauge housing pieces should be facing in towards the center of the clear
plastic, I sprayed the Alcad2 on first, and then the black on top of it.
The area where the light enters and also where it exits the plastic pieces
needs to be masked off before painting. I was really surprised at the final
result. It should work at least as well as the original chrome coating, and
it cost less than $10 to do.

Mike Schmidt
'88 928S4 Auto Black/Black "PORSCHE" cloth
928 Owners Club Charter Member
PCA Chicago Region









From: Joseph V. Maniaci [mailto:jmaniaci@houston.rr.com]
Sent: Wednesday, December 04, 2002 8:16 PM
To: 928
Subject: [928] Re: Instrument Light Problem


Chris,

When I got my car last year it had exactly the same problem.  When the
lights are off, the instrument pod lamps are at full-intensity.  When you
turn the headlights on, they dim in brightness automatically.  Mine just
went off completely when switching on the headlights.  The dealer fixed it
very easily.  It turns out that there is a series of resistors that are used
to dim the lights, and they are run in the circuit when the lights are
turned on.  When one or all of them go bad (open) it breaks the circuit, and
the lights don't work at all.  Probably less than a $200 repair at the
dealer, and not a difficult fix for someone with a little time, knowledge,
and an ohmeter.

Hope this helps!

Joe Maniaci
Houston, TX
'91 GT



From: Wally Plumley [mailto:wplumley@bellsouth.net]
Sent: Wednesday, December 04, 2002 10:51 PM
To: 928
Subject: [928] Re: Instrument Light Problem


Chris,

Check at D21 on Page 97-317. One of the black/blue wires runs from the 
instrument light pot to the resistor, and from there to terminal 14 on the 
pod. Check the resistor.

Page 97-333 says that it is under the pod.

Wally Plumley
928 Specialists