I have a 1992 CX (without a factory tach) with a JDM H23A. I'm using a P28 ECU. Well, I've searched on here, and I've seen a few different ways to wire one of these tachs (specifically the green wire).

There is a blue wire on the distributor, one behind the guages, one on the drivers side strut tower, and one on the ECU. I can get everything on the tach to work (illumination and shift-light) except I can't get a RPM signal.

I've tried running the green wire to the blue wire on the distributor and also to the blue wire on the drivers side strut tower, but I still can't get a signal. I'm starting to think that maybe my tach is messed up...although I did buy it new Let me know what you think...thanks!

 

Thats where I wired one up on my buddys b16 swapped EF so i guess check for breaks in the wire and good connections all around. That is where I believe they tell you to put it in the instructions. You can also follow the wire from the dizzy to the ecu and do it inside the car for a cleaner engine bay.

 

Look on your driver side strut tower. You'll see a harness there. Look a little behind it towards the firewall. You'll see a SINGLE BLUE wire with a little plug at the end. This is the jump wire for to get an RPM signal. Cut into this wire and solder in. There's your RPM signal. 12v, Ground, and Illumination I found all behind the cluster from the cluster harness using an electrical current tester.

 

red is 12v
white is for light switch
black ground
green for signal output from dist

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Dimi &raquo;</TD></TR><TR><TD CLASS="quote">Look on your driver side strut tower. You'll see a harness there. Look a little behind it towards the firewall. You'll see a SINGLE BLUE wire with a little plug at the end. This is the jump wire for to get an RPM signal. Cut into this wire and solder in. There's your RPM signal. 12v, Ground, and Illumination I found all behind the cluster from the cluster harness using an electrical current tester. </TD></TR></TABLE>

pic supplied

black ground
red 12v switched
white lights
green is tach lead.
i hook all mine up here.
the blue wire goin to nothing. at the left side strut tower.

 

Pic is a bit blurry. Let me take a shot of mine, and I'll post it in a few minutes.

 

Here j00 go:



and

 

I just hooked up my tach with the wires behind the cluster. Didnt have to run any wires from the engine bay.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Tyree &raquo;</TD></TR><TR><TD CLASS="quote">I just hooked up my tach with the wires behind the cluster. Didnt have to run any wires from the engine bay.</TD></TR></TABLE>

doesn't this defeat the purpose of putting one of those big 5" ugly things in your car? don't you put them in to "get a more accurate reading" instead of coming out of the ECU pinouts?

 

I had no tach before

 

When i hooked my tach up long ago i ran a wire to the distributor when u take the cap off you can see were to put it the first time i had a fiting on it and it would'nt get signal so i just wraped the wire around the screw,I remember my friend ran the wire for the light for the tach to the fuse box with the fuse for the parking lights its been so long i can't remember how i did all of it but i hope that helps a little

 

my head a sploded at work today, hope that helps (in the voice of Radio)

http://cupogoodness.net/MP3/barney2pac.wmv

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by citrEK &raquo;</TD></TR><TR><TD CLASS="quote">

doesn't this defeat the purpose of putting one of those big 5" ugly things in your car? don't you put them in to "get a more accurate reading" instead of coming out of the ECU pin outs?</TD></TR></TABLE>

the inaccuracies are in the tach itself. not the signal wire. the negative side of the coil has the same signal as the tach input to the ecu.

 

Thanks guys! I tried hooking up the green wire to the blue wire, but it still doesn't work. I think my tach may be messed up

 

I JUST WIRED ONE UP IN MY DX THERE WAS MORE THAN ONE BLUE WIRE SO JUST CHECK TO MAKE SURE U HOOKED IT UP 2 THE RIGHT ONE .. I THINK ITS THE ONE ALL THE WAY 2 THE LEFT

 

yea all the way to the left.

 

To the left of what?

 

there are also three small wires hanging out of the back of the tack that you have to cut the right ones to be sure its able to run on 4 cylinders, if you dont do that, it also wont work, otherwise its the blue wire behind the cluster.

 

I cut both of the wires on the back of the tach (as recommended for a 4 cylinder), and I've tried hooking up the green wire to the blue wire on the dizzy, as well as the blue wire on the strut tower.

Some people are saying that there are two blue wires (one all of the way to the left). My question is to the left of what???

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by whatsgood &raquo;</TD></TR><TR><TD CLASS="quote">I JUST WIRED ONE UP IN MY DX THERE WAS MORE THAN ONE BLUE WIRE SO JUST CHECK TO MAKE SURE U HOOKED IT UP 2 THE RIGHT ONE .. I THINK ITS THE ONE ALL THE WAY 2 THE LEFT</TD></TR></TABLE>

Hey! Take a picture of this "second" blue wire, would ya?