3000teeth

I've fixed all the electrical issues outside of the instrument cluster, so my next step is to pull the pod and go after the many problems there.

Here's a breakdown:
1. Warning light always flashing (could be a non-related).
2. Intermittent lighting of all the textual warnings on the cluster, including the low power and low fuel indicators (brake fluid light flashing).
3. Fuel gauge seems to stick sometimes (seldom).
4. Voltage indicator vibrating below 12V (I have brand new battery).
5. Odometer stuck (trip works intermittently).

Any suggestions on where to start would be greatly appreciated.

Thx -T

ROG100

Once you get the cluster off you will need to check the general condition of the foil circuit board. Clean the 3 connection points to the wiring harness with a pencil eraser. Reconnect and check out any improvements.
Look for a set of grounds behind or underneath the cluster and again clean and check them.
If the CB looks bad you may have to replace it. It is still available and is 928 641 939 00 and I have one in stock for $94.95. 928 Spec and 928 Int also would be a good source.

Mike Frye

Also, the stuck odo is probably the gear. Do a search on the odo gear and you'll find some good write-ups. This was one of the first jobs I did on my car and it wasn't difficult at all using the write-ups here.

Interestingly enough it's one of the few jobs I've only had to do once, so take that FWIW.

j.kenzie@sbcglobal.net

Sharkskin has a nice write-up (and website) and I have found his information extremely helpful.

http://members.rennlist.com/sharkski...icalRefurb.htm

3000teeth

Doh! Yeah, Dave's site is usually the first place I go when faced with any task --missed this one (eyes getting old, screen too big, gotta hit Ctrl++). Thx. And especially Thx to SS.

Yeah, and probably cheap enough that I should just get the replacement.

Thanks Roger. Good price. BTW, just mailed parts I didn't need back this morning --will PM you with new order.

Optimator

Sharkskin mentions the the odometer & speedometer pcb/rivet connections in his writeup. You may also want to read the following thread, in relation to your intermittent odometer problem:

https://rennlist.com/forums/928-forum/83767-dashboard-gauges-new-odo-gear.html

I would add that if the odometer works intermittently, then the gear is probably still intact. However, WYAI it may be a good idea to install a quality replacement gear.

Jim bailey - 928 International

Buy a circuit board while you still can ...the one for the 1982-1984 is no longer made nor is the 1978 BUT the 79-81 is STILL available for NOW ! I bought one for the old very brown 1980 because one day Porsche will be on back order then they will stop making them it is just a matter of time. Then you really are "Clusterf**ked!"

3000teeth

So I cracked open the pod today, pulled the cluster and took it apart. I found my OD problem to be caused by a cracked gear that connects the trip to the OD. I tried a ghetto fix with epoxy, but it cracked again as soon as I put it back on.

I scoured the circuit board and connector plugs as best as possible (considering how fragile it all is), and found my main problem to be that the plastic tab (left side, top) that a connector wraps around is gone. I fabricated a new one from a cut-up CD case (same width), but when I put it all back together, it doesn't look like I fixed anything.

I'm going to order a new circuit board, but what I really think I need is a whole new cluster housing, at least the rear. I don't see this part available anywhere --do I need to buy a whole new instrument cluster? What's that cost?

-T

3000teeth

I went back in and jiggled the "rigged" tab around and am actually seeing some improvement. Everything is brighter and my high-beam indicator now works. Stop light indicator shows up when I first start the car, then goes away. Brake fluid light blinks, but the fluid level is a little low. Warning light still blinks, but I'm hoping that's due to low brake fluid (will know tomorrow when I refill). The voltage indicator is still vibrating and the light is on.

3000teeth

Ok, that did it -no more warning light or brake level warning -parking brake light works too. Only issue I seem to have now is that the voltage indicator twitches when something else is pulling current (like a turn signal), but I think that's outside the pod.

User 4221

Did the symptoms first start when you were accelerating or braking?

Check the wiring harness that runs from the jump-start terminal across the engine over to the alternator block.

In this harness you will find oil level, oil pressure and the a high-current charging line. Over time the insulation breaks down on the wiring causing them to touch. Initially this begins under braking/accel.

My '81 did this and I had to rebuild the wiring harness..... Then all was good.

rcoble

I don't really see the panic with the lack of supply of circuit boards. I had a bad one on my 80 and I just soldered in wires instead. Its not that complicated of a thing. The circuit board was not needed except to seed up production.

3000teeth

Well, that was short-lived. One bwaaaaah, and the whole thing lit-up again like a high terror alert. I guess my cut-up-cd-case-fake-tab-fix vibrated right out. dammit!

Answer to your question Scott: When I first start it and drive down the block, the voltage indicator is around 10v and if I put the turn signal on, it jumps up and down in cadence. It used to just move around from the low brake fluid light blinking. Once I get it on the freeway, it goes right up to 12v or a little higher and stays there until I get back into stop and go traffic.

I'll check those wires. Thanks for the tip.

-T

3000teeth

Certainly makes sense and I could see myself doing the same thing --except I'd have to weigh paying Rog $95 vs. a whole Saturday inhaling lead fumes.