I have a 2015 1lt with no navigation. Recently the DIC lighting went very dim but all display functions work. The interior control **** works for the speedo and tach but will only make the DIC lighting even dimmer but not brighter.Hitting "settings" and then "display" on the DIC does not produce a "mode " setting to control brightness. I believe this is only on navigation cars. I have been told the problem can be: screen; human interface module; control switch [faceplate]; or issue with voltage going to led lights in display. Local chevy dealer who sells 1 or 2 Corvettes a year, reflashed an updated human interface module and this did not help. He contacted GM technical assistance who told him to replace screen. Any advice would be greatly appreciated as I don't want techs unfamiliar with Corvettes taking dash apart.

 

Any chance the light sensor on the dash is blocked or broken? If that sensor thinks it's dark in the car it will dim the DIC automatically.

Just for the record my 2014 (with NAV) gets confused easily - the shadow of a tree is enough to make it dim the DIC. Now what is odd is it can take several minutes in full sun - long after the auto headlights have gone turned off - before it switches back. Also the infotainment display doesn't always sync up with the DIC, so the radio will be bright but the dash dim. Even the HUD likes to play this game - its sometimes goes dim when everything else is bright or vis versa

 

Appreciate your reply but I believe the light sensor is working since the speedo and tach gauges will change depending on the outside light conditions but the DIC lighting stays dim all the time. As an aside I lived in Coral Springs for 23 years.

 

appreciate your input but since speedo and tach get brighter or dimmer depending on outside light while DIC lighting stays dim, I think dash sensor is probably ok.