Porsche Enthusiasts Club Forum

I have recently bought a 1989 S4 and have had a weird problem since I got it : The instrument lights are ON when the lights are OFF, but when the headlights are on the instrument lights are OFF!! So no visible instruments when driving in the dark! I guess the switch has got some wires crossed. Can someone shed some light on how to sort it.

thanks

Van Nottingham UK

Hi Van, I think this was discussed on 928uk? I'm sure someone said that if you replaced the lamps and put one in the wrong way round, it reversed the operation. Did the previous owner replace the lamps? Or has this started during your ownership.

How is the car? Are you getting out and about in? Mine was more comfortable than my 944, so I think it is a wise purchase.

I really like the car. Much more comfortable than a 944. I bought the car from Malton Specialist cars and it has done it all the time I have had it, which is not long. I am not sure I understand what you mean-are you saying that replacing an instrument bulb wrongly can cause this to happen. How? The light switch turns the lights on an off correctly but the dash lights are only illuminated when the lights are off. I thought that somehow the switch was wired in incorrectly. Since the car is under warranty from Malton I'll ask them to fix it, rather than mess with it myself. I am just curious.

Van

I'm not 100%, but yes, fitting a bulb the wrong way round could cause this. The guys at Malton should fix it for you no problem.

Thinking about mine, I think there was a dimmer for the pod lights. Could it be that they're fully dimmed while the lights are on? I'm sure someone with an S4 will be along soon.

On your digidash 1989 the dash lighting is always on, regardless of headlights.

As Lee says operating side/headlights will dim the dash lights. Have you adjusted the dimmer to max setting (thumb wheel above your left knee).

Do you have owner manual?

Hi, yes I have the owner manual. The dimmer has no effect. When the headlights go on the dash lights go off and stay off, however I adjust the dimmer.
Before i send the car back for a fix, will a squirt of WD40 into the dimmer do any harm
Thanks

Disconnect dimmer and short the wires together. Does this restore lights when headlights on?

Thanks-As the car is under warranty I'll leave that to Malton, especially as I have seen that to get at the switch there is lots of dismantling to do.

Van

Good plan Van if it is warranties.

The dimmer does come off with just couple of screws - no need to dismantle pod. Just needs a short screwdriver to give access and some grubbing about in footwell!

It was the dimmer-all fixed now..

Glad to hear it Van. I need pictures of the car though. It sounds a cracker.