Posted 4/26/2009 09:18 (#693150 - in reply to #692590) Subject: Re: How do you diagnose a JD tach in a 4455?
Check the plugs in front of the firewall. I had a plug where one of the wires was not installed correctly into the plug and it would not make connection. It was lights ont he back of the cab. Looking for a bad wire, it ended up being a plug that was not put together correctly. I pulled the plug apart to check continuity between two points and walla there the problem was.