My instrumentation lighting all works fine with the light switch on, but if I use the Auto Lamps, I have no instrumentation light at all??, looking through the shop manual, I'm a bit confused, it looks like it's all on the same circuit regardless...

That is strange... your auto lamp and your light switch both make the dash lights work, dash lights and heater lights ect. should be able to be adjusted with dimmer switch no matter if it is auto or manual dash switch is on.
Are you sure the head lights are on when you go to auto ?
Maybe Try messing with the dimmer switch somtimes when I switch from auto to manual my dash lights will flicker.

Nope, the dimmer has no effect whatsoever with the Autolights on, I have nothing but headlights..., if I turn on the parking lights, the dimmer takes over, otherwise it's just the message center and heater lit up full. :confused:

otherwise it's just the message center and heater lit up full.
You have no dash but have heater and message center lights while on auto ?
But when you turn on the manual switch to head light you have dash and heater ect ?
That is strange ...are you just turning on parking lights or full head lights when you use the manual switch ?

I've used the manual switch from day one, the heater and message center lights come on with the ignition switch, in auto lamp there is no gauge illumination whatsoever, everything works fine with the manual headlight switch.

The heater on and off or temp setting comes on with ignition switch.
The buttons on the bottom of the heater air control should come on with headlights and work with dimmer switch.

My instrumentation lighting all works fine with the light switch on, but if I use the Auto Lamps, I have no instrumentation light at all??, looking through the shop manual, I'm a bit confused, it looks like it's all on the same circuit regardless...

I am starting to have the same problem. What did you do to resolve this?

I haven't used the Auto Lights since I've had the car, I tend to susepct it's in the dimmer switch.

mine are kinda funny too, the dash lights only come on when its dark enough to need them. i dont use the autolights but its like the dash lights are still controled by the autolamp module, i thought it was normal, maybe its a gen 2 thing

Mine are strange as well, when the headlights turn on when it gets dark the instrumental cluster, message center and climate control are super dim. If i turn the headlight switch on, I lose my headlights but the instrumental cluster, message center and climate control are illuminated. weird!!!!