First you need to determine if the meter is bad or not. You can take a multimeter on the lowest ohm's setting and just touch the leads of the meter. It should defect the meter. You may have to reverse the leads to get a positive movement. Just touch the meter, don't hold the leads on the meter for an extended time. You just want to see if it moves with voltage or not. If its good then we can look at way it isn't moving. My initial thought would be a bad transistor, but could also just be dirty switches, old caps, broken wire, bad solder joint, etc.