These things used to be very bright during the day and I could actually read my speedometer. Now they are... not...

@houtex or anyone else that still lurks here - do you know of any adjustments to the "daytime" white LED brightness that I might have overlooked?

 

LEDs don't dim. They either work or they do not. Oh, there's outliers, but not the entire board's worth in the gauge cluster. It is my *guess* that they're being directed to be dim, which ostensibly means your dimmer **** on the headlamp switch is either set low, or the electronics thereto is faulty. Of course, you'll want to test things before buying a new/replacement dimmer switch/headlamp switch assembly.

The other cause is the driver of the LEDs in the gauges board is faulty and you'll have to have it fixed/replace the gauges.

I've looked at the wiring schematics of the instrument cluster and lighting, and there's no specific items regarding the instrument cluster LEDs. It is therefore handled internally to the cluster board and the CAN is used to tell it what settings the headlamp dimmer switch is asking for.

Again, *guess*. It's overall a 'simple' situation on the S197 Gen1s on this, but proving it out if it's not a simple problem causing it will be... fun.

I might be inclined to go find a wrecked S197 with the same gauge and go get that and the dimmer switch, and then plug them in to see what happens on the lighting. Switch first, then gauges. Don't run the car, just turn on the lights and see what you see. 'Course I dunno if a gauge can be gotten for cheap...

There's my 2 cents, but I dunno what that is in today's money as I dunno when the 2 cents thing was established. Hope it helps anyway!