just a thought. maybe its the gauge in the dash. do you notice if the temp in the car has a effect on it working or not? the reason I mention it is because in my truck when ever it is cold in the cab. like if I have the a/c on the odometer is blank. in the winter it is blank until I put the heat on and it warms the cab. then it will come on. mine is the solder joint that needs to be redone in the circuit board. just wondering if the inside temp in your car makes any difference.