Ed Taylor

Chasing a dash light problem. Does anyone know the pin designations on the back of the switch? If I read them correctly and my guesses:
30- main bus 12v
30b- ?
58L- left headlight
58R- right headlight
58- headlight motor
56- ?
57- ?
X- ?
31- ?
15- ?
Lost the dash lights last night, headlights, exterior lights and center console lights still worked.
Fuse and dimmer check OK.

87 S4
Thanks, Ed

Alan

What problem are you trying to solve - the switch is a very unlikely source of problems on this car. It does not switch the lights or headlight motor directly... don't mess with it if you don't have to...

Your guesses are not so good... its complicated and none of it works via that switch alone.

Alan

Ed Taylor

Alan, Pod illumination went out on drive home last night. Center console illumination remained on. Dimmer and fuses check OK.
Thanks Ed

Lizard928

how did you test the dimmer, I would recommend jumpering it to bypass it. That is normally where the issue is.

Alan

Ed the switch output that drives all those dash/console lights is the same one at the switch - means its not the switch. Jumper the potentiometer, check the dash/pod connections.

Alan

Alan

For Reference:

30 - Battery Supply(in)
30b - Switch Output - on only with light switch in 0 position
58L - Left side marker light supply
58R - Right side marker light supply
58 - Interior lighting supply (dash/console etc) non-dimmed
56 - Headlight feed to High/Lo Switch - direct for Aux high beam only
57 - Feeds "marker lights only" indicator in pod (single warning bulb)
X - Accessory Power (in) - on with postions 1 & 2 of ignition (0-3)
31 - Ground
15 - Ignition Power (in) - on with positions 2 & 3 of ignition (0-3)

Some of these features seem to make no sense unless you look at the rest of the configuration. It is significantly more complex than most cars. However the interior lighting is simple - a single switch output, direct drive, some via the dimmer.

Alan