PRNDL lamps go out when parking lights are on
 

That's correct....the PRNDL shift lamps illuminate fine, until I turn the parking lamps on. At least this happens most of the time. At times, it seems that the PRNDL lamps correctly dim once the parking lamps are on, but usually the lamps extinguish. Any ideas as to what would cause this? Is the issue in the headlamp switch ? The headlamp relay? Or perhaps the instrument panel circuit?

The fact that they work is good, but in addition to the mantra -Did you check/refurbish your grounds-

Do the other lights dim as expected?
Does the lighter lamp light up as it should?
Did you check the connector in the rear hatch? On my car its a multi-wire square connector under a plastic cover in the rear tire cavity.
I would disconnect and check the wires there. On my car they are a bit fragile looking.
Clean them up and then reconnect these wires (cant hurt..)

Oh and congrats on having an S3- We have the best of the breed man.

Possible bad connections in the ignition switch.

Did you rotate the dimmer wheel under the left side of the to see if the rheostat is clean and set to the tbrightest setting?

The PRNDL circuit is complicated. The PRNDL lights should come on with the parking lights OR putting the ignition switch in position 1 or greater.

Based on your problem it looks like the ignition switch is working. Power to this circuit comes from two pole switch on the bottom of the steering wheel lock shaft.

Do your parking lights actually come on? All of them? There could be a short in that circuit that is putting a ground on the PRNDL light circuit that makes them go off.

A more complicated problem would be a problem on the Tachometer circuit board. There is circuitry on that board that powers the PRNDL light circuit via the cable/connector in the rear tire wheel based on whether the parking lights are on or the ignition switch is on.

Hope that helps.

Yes, all the parking lights work and the lamp monitoring computer seems to work properly.

I did clean the contacts in the connectors in the wheel well, as well as cleaned the ground connections in the wheel well.

I also have played with the lamp illuminator dial under the dash and the symptoms are unaffected. Dash lights, BTW work properly otherwise.

ok. Do the PRNDL lights come on with just the parking lights? (ignition off)

On THIS note...just picked up my 928, today, 9/28....and I have no PRND32 lights either, and the rheostat works 90%, the last 10% to bright, and the dash lights then go dark..but no gear shift lights anywhere.

There are no lights at the gear shift, only the ones in the pod.

I just solved my PRND32, and no reverse lights issue I've been chasing for a year! I replaced the safety neutral switch, bulbs, cleaned all the ground points, fuses, relays, etc. It turned out to be the cluster, I replaced it and bingo everything works.

Dan :burnout:

Sorry Dan...."cluster"? What do you mean?

And BTW: yes, PRNDL works perfectly with parking lamps off. They just (usually) extinguish with parking lamps on.

Yes, I realize that. The PRNDL lights should work with JUST the parking lights on and the ignition off. Do they?

Also, Dan's comment about the backup (reverse) lights reminds me that the circuit that powers the PRDNL lights also powers the backup lights. This is because they share a common item, the PRNDL switch on the side of the A/T. I wonder if you have backup lights when your parking lights are on. You should check that.

Huh..well, all work on mine..dimly, except R and 2.


Just seemed..obvious somehow, that the shift area itself should light up.

OK BOb, it took some experimentation to get the whole story, because the PRNDL light and backup light outages are intermittent. Here is the way its operating:
1) PRNDL lights work with parking lights off every time
2) If the PRNDL lights stay on after turning on the parking lights, the backup lights work as well
3) if the PRNDL lights do not stay on after turning on parking lights, then backup lights do not work, as well
4) and as I recall, at those times that PRNDL lights and backup lights fail together, backup lights do not work as well when the parking lights are off...this one is "as I recall"

Hi Mike:

Without looking through the wiring diagrams, I'm wondering if the ignition switch connector is loose or the switch is intermittent. The switch that I'm talking about is not the main ignition switch but the small single pole switch under the dash on the ignition lock shaft. If you look under the pod you can't miss it.

Verify that the connector pushed in all the way. If that doesn't change anything, then test the switch with a voltmeter. See what you get and let me know.