my tach stopped working after I so bravely hit the wiring harness with a drill near the ignition control module. I cant figure out if its the tach or the box. what test can I do to test each?? I dont think I have a pulse signal from the box. Any help would be helpful. Post or email me at englatona@netzero.net

 

Check first to see if you ripped the wires in the harness.Unwrap the harness and make sure there aren't two wires side by side with insulation tore that could be shorting with each other.You could also have blown a fuse.

 

Yeah, tied that, didnt find any broken wires, and any fuse for the tach would knock out the dash( which is fine). I even found the wire for the tach pulse in the harness & ran a bridge wire to the tach but nothing, I am trying to find out if the tach can be tested some other way or I can put a tester on the box

 

Do you have a service manual? It may have instructions for testing the guage cluster.