tording92lx

Anyone have the Zex window/traction control switch? I have one I just bought new and I have it all hooked up. I am having trouble getting an accurate tach reading on it though.I have the green tach wire connected to the negative side of my coil right now but the reading on the window switch is very erratic. I have the tach setup on the window switch itself set to 08. Is this correct? Also where else can I tap into to get a reading for the tach? Zex tech support recommended at the ECU but I have read on some other forums that this could cause an issue becasue of the 22k ohm resistor in line before the ECU. Anyone have any experience with this window switch?

AdderMk2

you probably have a very dirty connection. How did you make the tap?

tording92lx

I have tried two kinds. I used a spade connector and slid it down into the coil at first which is how the aftermarket tach that use to be in my car was hooked up, and when that didn't work I then tried just a standard splice connector and spliced into the negative wire. I don't know how else a connection like this could be made.

AdderMk2

egh.... newbs..

that splice connector you used has sucsessfully cut part of your wiring

remove the connector, use a razor balde to remove the insulation around that area
connect the two wires together and SOLDER it

tording92lx

I love how everyone always assumes everyone is a newb. I have actually been into/owned/modded mustangs for over 7 years. I built a custom twin turbo car that made near 700 hp so I hardly consider myself a newb. I used splice connectors in quite a few applications on the turbo car and never had a problem with any of them working. I seriously doubt thats the problem here. Your probably gonna get pissed like most people do when confronted but to assume every person who is new to a forum is a newb is pretty ignorant. I will try the soldering method since you were nice enough to suggest it when I asked for help but it really doesn't help people any to tell them they are a newb when you know nothing about them. Thanks for the advice, I will give it a shot today. If this doesn't work anything else I should try?

AdderMk2

I called you a newb because anyone with any real experience would not have done such a hack job trying to wire in the window switch. Myself personally, I would have used a piece of shielded core wire and tapped into the wiring harness at the ECM. Thatway there would be less electronic interference to make the RPM's fluctuate so much.

but what do I know about electronics... I only built my own stand alone

tording92lx

In my first post I mentioned that but was curious about what other issues this could cause because of the 22k ohm resistor between the ECU and the coil. I am not saying you don't know what your talking about, I am sure you do based on what I have read from other posters. I am just saying that is probably 99% of all situations a tap in connector will work just fine, I know this because its generally how I do it and this is the first time I have had an issue like this. This may be a hack job in your opinion but if it works and it is easier then why not do it? So you think I should tap into the ECU then? I have a schematic of my wiring and it looks like the tan/yellow wire that goes to pin 4 on the ECU is the spot but like I said there is that 22k ohm resistor in there. Will this cause any other issues with the ECU like codes or anything or miscalibrations on the stock tach? thanks for the help.

AdderMk2

it should not affect the stock tach at all and you should have a cleaner signal

tording92lx

fantastic. Am I correct then that I shouldtap intothe wire that goes to pin 4 on the ECU? This is the schematic I used. Also where is the best place to pick up some shielded wire? I am guessing radio shack maybe?

AdderMk2

yes, I would say (based on that diagram) that pin 4 should be the one your looking for