syoo8

On my 86.5 928S, the central warning light (underneath the HVAC, above the clock) will not reset when I push the button.

I looked at the wiring diagrams but it is not clear to me what has to go wrong for this symptom to occur.

Other symptoms are that the clock does not work (although the illumination works just fine.)

Any ideas as to what this could be? I searched RL and could not find another instance of this.

Ducman82

so its lit up, all the time? anything on the dash after start up? any other resent work?

syoo8

Hi Ducman

The central warning light turns on as it is supposed to. For example, when the gas is nearing empty. Otherwise it is off.

No there wasn't any recent work. I was thinking it was a grounding issue, but the problem seems to be the power supply to the clock, not the ground.

MainePorsche

Power to clock unrelated to central warning system or the panel above the clock.
Check fuse 24 for the clock.

syoo8

If fuse 24 were blown wouldn't that also shut off the clock's illumination?

WallyP

No - the clock illumination is on the instrument illumination, so it can be dimmed, turned off, etc.

syoo8

Wally- thanks for your reply. Your treatise on the HVAC system is my nightly reading, as I will tackle it when I return from the business trip I am on now. Have you ever encountered a central warning light that will not reset? Did the switch just die?

joejoe

on one of my '86.5's I will get the '!' and it is from abs fault. Eventually the warning on the dash pod will go out and then the '!' also goes off. Do all warning light light up with key in on position before starting?

MainePorsche

Before considering sensor faults, have you done any work under the console recently ? The connections on the back of this particular panel are very tenuous, and the connecting wires are of very small caliber.

CraigL

Do all of your instrument panel warning lights work?

It is possible that one of these bulbs is burned out.
And it is possible that a real error is occurring at that function.
You won't know since the bulb is bad.
But the Central Warning light will be on.

Turn the ignition key to the 1st position (engine not running).
Take an inventory of the warning lights on the instrument panel.
Any not illuminated?

syoo8

Update, January 30, 2014

Sorry to dredge up an old threed. I am trying to tie up loose threads on Rennlist that I've started.

This problem of the central warning lamp not resetting has been solved.

There was a short circuit in one of the interior lights (the one next to the hatch.) For some reason, it was causing all sorts of other problems- including the central warning lamp not resetting.

The stock interior lights are famous for being finicky and for easily shorting to ground (i.e. the body.) I have solved that by buying replacement interior light fixtures for (I believe) a VW Passat from Roger. He has them in stock, and they are far superior to the chintzy clear plastic fixtures that came with our cars.

Bilal928S4

GREAT.
Thank you for posting the solution for future adventurers.

syoo8

No problem Bilal.

Over the last 6.5 years, I've read almost every thread on the 2012 pages of Rennlist 928 forum. I've found that people often do not post when their problems have been solved, and what the solution was. I was guilty of that, hence the update.

SteveG

But it is so good that you posted the solution. Thanks.

Mrmerlin

Thanks for posting a solution, it makes it easier to fix things later.