Originally Posted by Russianblue

it's the button you press when you get a check control warning to make the warning go away. so....on the instrument cluster, two buttons - one on the left and one on the right. I always called them the trip meter reset button (left) and check control button (right, btw the tach and temp gauge). That might be a carryover from my e28 days now that I think about it, LOL!

not sure if I have the high or low cluster. need to figure out which one is which!