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tach wiring.

I've been trying to figure out this tach wiring issue.
I believe the correct pinout off the back of the gauge cluster is pin#13 on connector c-50 for the tach signal.
if this is correct, where do I run the wire to?
the wiring diagram I have shows that it goes to the ignition power transistor.
the ignition power transistor I have has the 1g style 6pin connector

Im looking to hook this up directly to where the signal originates from, I don't want to make any wiring splices near my ECU.

its the original tach in the instrument panel that Im trying to get to operate again. im trying to find a place to terminate the other end of the wire. the wiring harness in my car is two different harnesses spliced together. I looking for a more direct route to wire it. supposedly there's and inline filter that this signal runs though as well. any clarification on this would be appreciated.

The transistor is either a 5-pin 1990-style transistor, or the newer 1991+ 7-pin transistor. What year is your car/tach? What year is the transistor? What year is your ECU? Only 1991+ transistors have the extra TACH output.

the trasistor is the older 5-6 pin version. the gauge cluster is a 90 as well...looking at the electrical drawing I have, for a 90, it seems the tach signal came from pin 3 of the 4 pin ignition coil plug. 91+ cars only have three out of four wires going to the ignition coil plug and pulled the tach signal from the transistor instead plug instead. if I T'd off a shielded wire from pin 3 on the coil plug ad ran it straight to the tach, do you think it'll work?

On a 1990, the TACH signal comes from a separate "TACH DRIVER" module that is on the coilpack. It has 2 wires, one for each coil, and an output wire to drive both the ECU and the dash tach. You need to get a 1990 coilpack, or at least that separate tach driver module, to make it work right. Is the ECU also 1990?

the coil pack that I have has this connector on it.

supposedly the white wire going to pin 3 is the tach signal. I just want to be sure.

That sounds right, but you can trace the wire back and make sure it goes to a separate "TACH DRIVER" can attached to the coilpack.

You did. It shows the 1990 4-pin coilpack plug. As you said, the one wire in the plug is the tach signal, leading to a tach driver module on the coilpack.
In 1991, Mitsubishi moved the tach driver to inside the transistor instead, which is why the transistor now has 2 more wires, 7 vs 5, and the coilpack only has 3 wires now, instead of 4.

so if I ran a shielded wire grounded at one end from pin 3 of the coil and ran it to the tach input behind the instrument panel, that should be it? I have all the electrical diagrams for galants ,1g and 2g's...And, I know how to read them because I do it everyday for work, there just happend to be some missing info I needed cleared up.

see most people would just hook it up to whatever they think its should be going to, being an automation technician/electrician, im not that type of person, (something about not wanting to blow something up the first time, IDK) lol I cant tell you how many times I've have to rebuild or replace burnt-up wiring harnesses in other peoples cars because someone was reading the "universal" installation instructions to something. /ubbthreads/images/graemlins/rofl.gif

BTW....If anyone would like a copy of the DSM shop/service manual PDF's or parts of it actually (I will not give up all of it, too much stuff) that contains the "body/electrical" and "mechanical/chassis" for 89-91 and 91-93 galants or somthing for 1g's or 2g's...Let me know...ALOT of this information is incredibly hard to come by. the "body/electrical" portion itself is around 900 pages. but it shows you where every connector and termination is at.

I would also like to thank Jeff/Keydiver for helping me verify what it is that I was trying to do.

ohh yeah, hey Jeff, do you know if you or anyone you know here in Florida is going up to the DSM shootout in august? we're trying to get a decent sized caravan lined up. there's already about 4 or 5 cars with two people each for sure from bradenton and tampa meeting up. didn't know if you or anyone else you know is going. It's always nice to go in a big group, filled with DSM mechanics... /ubbthreads/images/graemlins/rofl.gif
we'll have a truck and car trailer and lots of extra parts too, if someone broke down and we couldn't fix it on the spot, it wouldn't stop us at all. we'll have more time to fix it while we're there.
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