NEED Help with instrument cluster issues.

[Dean_Fuller]

I have probably bored everyone with the original tread on Garrett's car. Most may not be reading that now so I will try here . I have Garrett's car almost complete now. The car starts, runs and shifts as well as it did 2 1/2 years ago when I started taking it apart. All exterior lights work as they should EXCEPT NO Brake lights.

After installing the instrument cluster and a test drive here is what is happening.

Temp gauge......pegs max hot right away.
Gas gauge shows 3/4 tank with 8 gallons in.
Speedo..............not working.
Tach..................works
alt gauge............not working
oil pressure.........not working
No gauge lights.
high beam indicator ON when regular head lights on, and OFF when high beams on.
Driving lights work but when ON the fog lights stay on too.
Also NO Brake lights.
Whippers not working.

I think all else works.

What I have tried.
Cleaned grounds under steering column twice.
Cleaned grounds at pass rear corner.
Cleaned main battery ground.
Checked all fuses.
Reseated all main connectors in fuse panel.
Reseated all relays.


The film on the back of the instrument cluster is dry and brittle. The three main plug ins had several contacts "roll up" and I re glued them down and scrapped off any glue residue on top with a razor blade. I cleaned contacts with a eraser and sprayed cleaner down into female plugs.

After reading Dwayne's write up on cluster repair he stated he had erratic needle movement after touching the back of the panel around the rivets. I tried that with no reaction at all in any needles.

I am not good at electrics...where do I start?

Is there a way to see it power is getting to the cluster lights?

With this much not working I would think its a ground or a short ( no blown fuses ) .

Any help, ideas would be great !!!!
__________________
89 928 s4 auto Slate / Cashmere ( mine )
80 928 auto Synergy Green / Black & gray interior ( son's )

[924CarreraGTP]

With a brittle or cracked circuit film, it sounds like you need to find a good used circuit film or better yet a complete cluster with a good circuit film. This is probably the problem. It's like any other circuit board. One break in the connections can cause all kinds of problems.
Come to think of it we talked a while back about parts. The '86 that I have has a good cluster in it, but I'm not sure if it will be exactly like the 1980 (?) cluster.

[Dean_Fuller]

Yep...I think thats the problem. I know later model film will not work. This one is worse than I thought. I don't think it can be saved. Anyone have a good 1980 model film laying around?

[gbgastowers]

I fixed everything on mine (speedo still does not work) doing something like this. 82 928s printed circuit board - Page 2 - Rennlist Discussion Forums . I used a breadboard (Radio Shack) cut with a dremel to what I needed to hard wire it and bypass the factory connection plugs. You can spend some time checking continuity on the entire printed flex board and repairing/soldering any breaks and then do the bypass or buy another printed board that might also be bad. Porsche 928 instrument cluster | eBay

[924CarreraGTP]

Is that an infamous 1982 federal regulatory 85 mph speedo? Yuck lol

[anakilat]

Do you have vertical or horizontal gauges? I have a horizontal gauge cluster I'm willing to part with from an 80 US

[Dean_Fuller]

Horizontal....I am interested if its in better shape. PM on the way. Thanks

[Illini-heel]

Originally Posted by 924CarreraGTP

Is that an infamous 1982 federal regulatory 85 mph speedo? Yuck lol

I have a 1982 Yamaha Seca 750 with that speedo, pin it in 3rd gear at about 1200 RPM.