Mongo

I checked Fuse 44 on the CE Panel and it's fine. The ashtray light illuminates and the LED for Parking Lights turns on. However, there are no dash lights or instrument cluster lights illuminating. 6 days ago everything was functioning. I know this car hates sitting, but what else on that circuit would cause inoperable lights?

Mrmerlin

check the rheostat under the dash on the left side of the steering column

velocipus

My rheostat had much corrosion. Wire brush and dielectric grease fixed the problem though now I have either on or off, no dimming.

SQLGuy

Sounds like you have a break in the wire that makes up the rheostat... the wiper is only making contact at "full bright" (where it hits the 12V supply end of the wire). Easiest thing would be to replace it.

anpo

Mine was like that when I bought the car. Rheostat was more or less melted and PO had disconnected it. Just created an s/c and now have full brightness all the time.

Anyone knows where to get a new and how much? According to PET they aren't available from Porsche.

Lizard928

it is the rheostat as stated.

On mine when they die I normally unplug and bridge the wires together.

Mongo

I usually like dash lights bright. I may just bridge it. I have new bulbs in there anyways and I like how bright they are.

John Speake

PET shows the dimmer pot as 928 613 121 01

MY 90: MG 9, SG 03, Page 903-00

anpo

^^Remark: -88

Since you mention MY 90 I assume it's meant for me and not the original question in this thread. -90 onwards is 928 613 031 00 which gets "Part number 92861303100 not in stamm". But thanks anyway

John Speake

Ah ! OK, so something changed with the introduction of digi-dash ? "part number unknown".

The rheostat for the later cars also comes up with unknown as well...

Have you enquired at a Porsche Centtre ?

anpo

No since I doubt I will find it worth the money, quite satisfied with full brightness. Was just curious if anybody know of an cheaper aftermarket look-a-like..

Spun

Old thread additional question.

On an 89 I am working on, I can get the cluster to go full bright all the time (headlights on or off) when I pull or blow fuse 44. When the fuse is good, I can use the rheostat or bridge the wires and the other lights work, but not the cluster... The cluster will be out with lights on or off.

Any thoughts?

Mongo

By any chance, are you getting good connections to the circuit foil? I pulled my cluster one more time to replace a burned out bulb, but upon re-installation, I couldn't get the lights to illuminate. I then removed the cluster again and 'reconnected' everything only to successfully have every bulb light up again.

Spun

I think so since I am getting lights on when the fuse is pulled, but since is changes from ground to 12V (I think) when the lights are turned on, I'm not sure.

I did short the lines to ground and that blew the fuse, but illuminated the cluster...

Could I be grounded in the cluster somewhere and thereby only having a ground illumination of the cluster?

Alan

Check fuse 24

Alan