2003 jeep wrangler, alarm/remote start

ive been reading the posts and they been real helpful. but i ran into a problem and i need to post my self. im installing a galaxy auto start alarm in my 2003 jeep wrangler, manual tranny - 2.4... in order to get the auto start part working i need to hook up the well known TACH wire. ive read here that its eather grey or blue with a tan stipe and that its comeing from my ignition coil. thats great but where is the ignition coil??    if someone can add some input on this be real apreciateddd. and once i do find it how would i test it if that is the actuall wire called TACH. thanks guys for all the help so far this stie is better then just great.   :)

You can find your coil by following your sparkplug wires starting from the plugs back to the coil. You can test for a tach signal by setting your digital meter to ac and probe the wire while the engine is running. The correct wire should show between 1 and 6 volts. The voltage will increase with engine rpm. You can also use a wire at one of the fuel injectors instead of at the coil.

i found that wire but i dont know if its the one going to the ECM. but it shows fourteen V while car running. bbtaco says it should show between one and six and go up when reving the engine which here its not the case. i found some other wires one had 2 volts the other six. but neither would go up when reved. my previouse car was a 86 mustang where everything was simple but here in this 03 wrangler i just cant find the ignition coil. is it mixed in there with something else or am i just that blind?? hey bbtaco what color do you say the tach should be. p.s. im about to take out my instrumental panel and run it from the RPM guage...     grrr thanks for the feed backs fellas.

to test for tach you need to be in ac volts not dc.

but thats the way to test for the tach mobilecustoms?? 1 to 6 volts and while reving volts go up??

When I put my Viper remote start in my Jeep with a 5 speed, I used voltage sense instead of tach. I found with some experimentation that in the event that your vehicle was left in gear, if you remote start it using the tach wire it is a lot more prone to driving itself across the street than it was using voltage sense instead. With voltage sense it kind of sputters forward a couple inches and stalls. Whereas with tach it would actually move several feet. (Like I said, this was with my own experimentation into the situation. I leave my Jeep in neutral always but just wanted a failsafe just in case.) Also, I'm not sure if that type of remote start can be programmed to voltage sense for that matter so my advice may be worthless.

hmmm    what is this voltage sense you speak of?? where on the jeep is it or is it not on one?? more details please :)       thats some worthful advice   thanks raab3485.

yes that is the way to test for tach. if it is a dei you can set it for voltage sense instead of tach.

well im going to keep looking for that tach wire. by voltage sense you mean the guage that shows how many volts the batt has in the instrumental panel. or is this something diffrent that once again i dont know anything about.