1985 300TD Tachometer (federal)

[dennislarock]

Hi... New member, new to Mercedes diesel, first post,

I have just spent about 16 hours (half the time on the internet) trying to get the tachometer to work.

What I've done:

Checked rpm sensor... receiving 5.67 volts at idle
Checked OVP relay... its receiving voltage and the fuse is good ...also, have 2 matching OVP relays from another 85 that definitely works in the other 85.
Checked EGR inside kickpanel... no voltage ...It has two wires going into it at the center pole and the pole directly above it. All other posts/poles are blank. The cap has the number 3 on it.

any ideas or is it time to tear into the dashboard?

Thanks

dennis