I've had my coach since new. I had a progressively worse and worse tach problem, jumping around to the point I was using the Aladdin to get the tach reading. I finally went into the generator compartment and cleaned all the wires connected to a common buss and cleaned the #6 wire leading from that buss to a frame ground. I sanded all the paint off under that frame ground connection and re-attached everything securely. Just finished a 1000 mile trip and everything works perfectly. Problem solved.
Bill & Brigitte
06 Windsor PEQ, Cummins 400 ISL
2014 Honda CRV or 2012 Jeep