Dimmed Backlit Dash and Radio/HVAC Lights

[EddieC]

My 2008 Tahoe backlite dash/instrument/radio/radio lights seem to randomly get very dim and a while later they brighten up to normal without any input on my part. This occurs (randomly??) during the daylight and I don't know what could be causing it or how to fix it.
Any ideas?

 

[Miami-Dade]

@EddieC Moved you here from 15-20 section.

 

[Shubbydog]

Sounds like a failing dimmer switch.

 

[Doubeleive]

could be the switch, should be cheap and easy to replace

 

[EddieC]

@EddieC Moved you here from 15-20 section.

Thanks, I missed that.

 

[mikez71]

Shouldn't it be the light sensor/circuit since the dimmer only works at night?
Does the dimmer dial work when it's dim?

Dim backlight has been bugging me more since I got a dashmat.
The sensor has a resistance of ~600ohms in direct sunlight, and 15,000ohms in full dark. Not sure the exact setpoint, but 10k will put it in dimmer mode IIRC..

I'm planning at least one of 3 things (maybe combo of all...)

1. switch with day/night resistors to manually select brightness (or mode)
2. relay with day/night resistors triggered by the parking/headlights
3. resistor wired in parallel from light sensor input to ground, to de-sensitize light sensor.