ImBatman

I am working through various bugs and broken things this weekend. I'm starting with replacing spark plug wires but that won't take long. Next on the list is the tach.

The tach was erratic just before it finally quit working and dropped all the way to the bottom of the display past the other rpm Mark. It no longer moves at all.
I have heard that this would not be a failure on the circuit board so I most likely won't have to pull the cluster. If this is true where do I start looking?
I have the factory service manual but can't find this. Anyone know the section and page as well as information on what to do?

Thanks!
Wade

WVZR-1

When "KEY-ON" not running does the TACH park @ 0? If not where?

If you have C68 AC what does the AC LCD display for values at various levels of acceleration - does it display anything at all? If no C68 you can't do this test!

ImBatman

I will check just turning the key. When I crank it the tach shoots past 6k and then immediately drops past 0. It never moves again after that.