How to get Tacho signal from EDIS6 module?

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speedy
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How to get Tacho signal from EDIS6 module?

Post by speedy »

Hi,

I had recently retrofit MSnEDIS on my 6 cyl car,using edis6 module.How to i drive my tacho with this module,it doesn't have CTO like the edis4 module.

I had also tried the" 3 diodes with a zener circuit",but my tachometer just won't response to it,wiring had been checked n rechecked.

Anyone had experience on these?

speedy
78Spit1500Fed
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Post by 78Spit1500Fed »

If your tach was originaly diriven from the coil - side, there's probably a current limiting resistor on the input. (To keep spikes from killing the circuit) If it's too large a resistor, it will keep the signal from passing to the counter.

You'll need to reduce the level of that resistor until it starts working. I would put a pot in line first, determine the value and then solder the resistor in.

-Brian
TurboCamaro
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Post by TurboCamaro »

So does this mean that the signal from the EDIS is too weak to make it through?

My tach was originally driven by the stock GM DIS and now, with the EDIS 6 it jumps around a little when the car is first started and then just goes low and doesn't respond.

If the EDIS tach signal is too weak can it be amplified to make it though to the tach instead of trying to find that resistor on the gage cluster?
-Wayne

1994 3.4L V6 Camaro 5 spd.
Custom Turbocharged/Intercooled
78Spit1500Fed
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Post by 78Spit1500Fed »

That's odd. I would expect the DIS to output a +12v square wave just like the EDIS does...

Do you have an osiliscope to measure the DIS output to see what it's giving your tach?

-Brian
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