cant get tach signal to work, help
Printed From: the12volt.com
Forum Name: Car Security and Convenience
Forum Discription: Car Alarms, Keyless Entries, Remote Starters, Immobilizer Bypasses, Sensors, Door Locks, Window Modules, Heated Mirrors, Heated Seats, etc.
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=25922
Printed Date: July 19, 2025 at 2:29 PM
Topic: cant get tach signal to work, help
Posted By: 95stangw
Subject: cant get tach signal to work, help
Date Posted: February 05, 2004 at 10:04 PM
I installed a prestige alarm/remote starter into a 96 toyota corolla. Initially i had a problem where nothing would turn on. I have resolved that issue, the alarm functions properly except for the remote starter. Im supposed to program the tach rate into the alarm, but i cant get it to learn the signal. Im wondering if someone has done alarms on this same car if they can tell me where they got their tach signal from? I tried every single wire on the distributor except for the power one. The wiring diagrams say its a black wire, there are 2 at the distributor but still the alarm wont learn the tach rate. I know that sometimes wiring schematics are wrong, so thats why i want to know if someone has done this car, and if so where did you get your tach signal from? This is the only thing stopping me from my first succesful alarm install . thanks to anyone who helps me out.
Replies:
Posted By: chriswallace187
Date Posted: February 05, 2004 at 10:27 PM
On Toyotas, a tach signal can usually be found at the distributor or the igniter; I'm not sure where the igniter is located on that year corolla, but usually it's on the driver's side fender or the firewall and it will say 'igniter' on it. You can also look for the test connector under the hood, and see if it has a wire going to the pin marked IG- , which is also a good tach signal.
If none of those work, than you can switch the remote start to work on voltage sensing (the instructions for the unit probably say that you have to have a tach wire, but then in the remote start programming section there are instructions to change it to voltage sense - go figure). I would strongly suggest using the tach wire though; I've never had much trouble learning it on a Toyota, and it's easier to learn the tach than to change the setting to voltage.
Posted By: 95stangw
Date Posted: February 05, 2004 at 10:49 PM
I will look into the test connector, would i expect to see it on the left side or the right side of the engine bay? Im sorry im so ignorant even though im a tech, but i hardly ever work on imports. Do you know what wire it should be at the distributor? as mentioned i tried all of them except power and nothing.
Posted By: Teamrf
Date Posted: February 05, 2004 at 11:40 PM
What kind of alarm is it? If you are having a hard time learning the tach...I would suggest you use voltage sense if that is an option on that alarm.
-------------
~The Rookie~
Rookie of the year that is...
Don't let the smoke out of your equiptment..it doesn't go back in.
Posted By: chriswallace187
Date Posted: February 06, 2004 at 12:09 AM
I've seen the test connectors at various places in the engine bay on different Toyota models, but they're hard to miss; they have a flip open top piece that says "diagnostic" on top and when you open it it has a diagram of what the pins are. As far as getting the wire at the distributor, I'm not sure if I've ever gotten a tach wire there. Toyota always used external igniters to supply the ignition system, and they're usually more accessible to get at anyway.
Posted By: mecpcert_1
Date Posted: February 06, 2004 at 3:43 AM
the diagnostic plug should be on the driver's side shock tower. that's where it was at on my '94. ('94-'97 is the same body style)
-------------
do it right the first time....less warranty work=more money!:)
Posted By: 95stangw
Date Posted: February 13, 2004 at 9:15 AM
Sorry it has taken so long for me to answer but i had to take an emergency trip out of town. I just finished installing the Viper 791xv into my mustang and it works perfectly fine, went without any trouble. Now the Toyota is a different thing, i still cant get a tach signal. I tried the Ign wire at the diagnostic connector and got nothing, I still havent tried the igniter and i want to know if anyone knows the exact wire that has the tach signal. If i do switch the remote start to voltage sensing where do i hook it up to?
Posted By: derek123
Date Posted: February 13, 2004 at 9:35 AM
You should use a digital mutli meter ( set to AC) and find your own tach wire. a tach will show you an AC signal while the engine is running, and will increase in voltage when the rpm of the engine increases. Don't get in to the bad habit of relying on others to provide you with information, find it yourself, and then you know its right.
Posted By: 95stangw
Date Posted: February 13, 2004 at 10:36 AM
derek123 wrote:
You should use a digital mutli meter ( set to AC) and find your own tach wire. a tach will show you an AC signal while the engine is running, and will increase in voltage when the rpm of the engine increases. Don't get in to the bad habit of relying on others to provide you with information, find it yourself, and then you know its right. I dont rely on others to help me out, its just that as of right now i dont really want to even do this alarm. I hate working on toyotas as im very ignorant as far as their wiring layouts go. On my mustang the diagram that is listed on this website and another that i got through an installer where wrong about the tach signal. I got my fluke multimeter out and found it myself, I had no problem with that. But on the toyota i have limited time to work on it, and i was hoping someone would know. If i had all the time i have with my own vehicle, believe me i wouldnt be asking.
Posted By: profuse007
Date Posted: February 13, 2004 at 12:13 PM
just try using voltsense if you cant get the tach to work.
toyota have two diagnostic connector, one at the passenger engine bay(rectangular flip box) and under the drivers dash(circle).
if theres a distributor, you can get it at the 4 wires connector.
the igniter is at the driver fender like someone mentioned.
-------------
Houston,TX
"The two most common elements in the universe are H+ and stupidity" (Ellison).
Posted By: sufferrar
Date Posted: February 13, 2004 at 1:36 PM
set you multimeter on ac and check for a wire that reads 4v to 6 volts when idle and rises when you increase in rpm . this is a sure tach wire ...
-------------
"I'm So Loud It Hertz"
Posted By: 95stangw
Date Posted: February 13, 2004 at 8:34 PM
I will try to find a tach signal, thanks for all the help
|