the instrument gauge will light up after the car has been turned off. It appears to be a short but dealership could not find anything. Car was hooked up to a voltage meter for a day and 1/2 and no pull. I read that if the radio is left on after the car has been turned off, that the car should automatically shut down the radio to avoid battery drain. I have already had to replace the battery
Why does my middle instrument gauge light up when the car is off? on 2010 Mercedes-Benz E350
by ssh in Bowling Green, KY on January 14, 2013
ANSWER by gmc4me on January 14, 2013
If the light was on there is absolutly no way that your battery did not lose voltage. I agree with it being shorted. That would need to be traced down.