2004 explorer & 791xv problems need help

I need help I have a 2004 ford explorer xlt & I purchased a viper 791xv. the problem that I am having is sometimes the vehicle starts normally other times the display tells me the car is on i go outside and the car is attempting to turn on but it does not. I had the same problem with a nissan altima that i had so the delearship told perhaps the alarm module was messed up so they charged me 80 bucks and it still does this and DEI aka directed electronics will not help me out because i am not a dealer. can someone please either post a solution or the wiring diagram for this alarm install on my car I need help bad I have two little girls that will appreciate the car being warmed up each morning for the winter. Thank you all ahead of time

which tach wire are you using?2005 Toyota Corolla S

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What exactly is the car doing? Is it attempting to crank? There is a factory led in the center of the dash in a transparent black dome. When you try to remote start the car does this light come on for 3 seconds and then go off? Or does it start flashing real fast? If it flashes fast then there is a problem with the bypass for the pats. The main wires you need are ign red /green acc BLACK/ green starter red and I do not remember the constant. You do not have to power up ign 2 or acc 2 for remote start. If it is not that, it could be a tach concern. Dei has several adjustments for their tachless operations.     

I have no idea about tach wires or anything I have someone here that knows more about this but he needs the diagrams cause i dunno anything

The tach wire from the alarm is purple with a white stripe. On the car you can go to an uncommon wire on the coil

so this PURPLE / white wire should go to tach wire? oh yeah someone also mentioned that this alarm can control my tailgate to add a relay is that something i can do? cause whats a relay anyway i am clueless to automotive stuff

so i went to the dealer today i was under the impression i was going to get the tach wire installed. little did i know that i was told they do hundreds of alarm install's and they never had the need to use a tach wire because he said these cars no a days are all computerized if you run a tach wire and you have problems where the tach wire shorts you can fry your cars ecu and then you will be out of luck. he also mentioned he is following directed electronics wiring diagram so what he tried was he pluged in this pda looking thing into the car alarms module box thing and he ran some diagnostic and then he changed the crank timing to 1.0 he told me to try that and see if it works right so i will be starting the car out everyday as much as possible to see if it does the same problem. is this information useful or are they still bsing with me

He is lying point blank. I bet he didn't even install a hood pin either. Here is the 791's install manual just so you know what is supposed to be hooked up. Also the PDA thing you are refferring to is called a bitwriter and has no diagnostic menu's at all, again if he said that he was running diagnostics then he is lying.Certified Security Specialist

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