996.1 Dash Lights Question

[36270k]

On my old Boxster the dash lights would go from bright to dim when the lights were turned on.

On the the 1998 996 I have just bought the dash lights stay dim all the time.

Any advice
Thank you P

[36270k]

Tried turning the adjuster, it seems to have no effect.

The lights stay dim all the time with the headlights on or off.

[36270k]

The milage and digital speedo lights stay dim all the time with the headlights on or off.

In sunlight the digital speedo is barely visible.

Mileage and Digital speedo LCDs seem to brighten up when the ignition key is removed

Any advice
Thank you P

[36270k]

Been advised that light switch may be faulty ?