Tach

[JPR]

Tach problem

Been working on the truck, went to start it yesterday and no tach. Checked the fuse and it is okay and has power. Replaced the pick up today and still no tach. Any ideas?

 

[turbo69]

Start at the tach senor and trace the wires back...

Are all the other dash gauges working?

Might be a bad ground to the cluster.

One other thing I would try would be to continuity test the tach leads all the way back to the cluster plug, then test the board plug to the tach.

Wish I had a drawing for ya, but I don't.

Good luck.

 

[JPR]

The answer to the tach question if you have an E4OD transmission - If you lose power to the computer, the tach will not function. That was the problem.

Both tach sensor wires go to the transmission computer, not the tach. The green/red wire goes in the left column 4 from the bottom, the tan/yellow 3 from the bottom. The computer sends out it's own signal to the tach, a white pink wire center row, 5 from the top.

The tach sensor should have a resistance reading of 2000-3000 ohm.

 

[turbo69]

hmmmmm-

ya figure I'd have known that one, huh?