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Tach connection

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Old 08-21-2018, 05:24 PM
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Default Tach connection

5.0 build using a FiTech efi system so I no longer have the ford ecu...

I understand the tach wire is yellow/blu at the cluster and also in the diagnostics box. Can I jumper off either of those points straight to the negative side of the coil ?

Is a resistor required ?

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Old 09-05-2018, 11:50 PM
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Hi,

use the Dakota digital universal tach adapter us ethe fti as the trigger and the Dakota to drive the tacho in the dash. It does the 8 to 4 cyl conversion for you.

It saves a lot of mucking around.

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Old 10-11-2018, 09:45 AM
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Ok, I should have mentioned this is a 1992 NA...

Dakota Digital SGI 8E tach adaptor installed. Power and grounds to unit are fine, the unit flashes the red dot dot like it is receiving signal no matter what configuration output I use. Tach signal in is being pulled of the neg side of the coil. The problem is my dash tach is non responsive. Tach worked flawless before the swap.

I have tried all the output options offered, high out, normal out, and a jumper between high and not used terminal. I am using the screw on the back of the cluster that goes to the tach as a connection point versus splicing into the wire. Continuity between that screw and the wire is fine so I am assuming that is ok to do.

2 calls to DD and I don't seem to be getting anywhere. I check the high output and it is putting out 14.39v dc, low is putting out 534mv dc (that seems wrong) I did get a 5.6v dc reading one time on the low side. Seems to me I need to be using the high output anyways.

Any insight ????????

Last edited by hotwheels000; 10-11-2018 at 09:49 PM.
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