icbm 7071 remote start

I installed this alarm in 2012 in my 2000 Chrysler Town and Country and it worked great until just after Summer of 2013. The alarm is working flawlessly however the remote start cranks the after a few seconds turns off then tries 2 more times repeating the procedure to try and crank. It gets cranked but acts like it cant see the tach signal. I tried disconnecting the tach wire from were I had it and it was working then connected it to an injector. Both connections appear fine with tach signal. I followed the tach wire and tested for continuity and it is fine as well. I was wondering if it would be ok to use the red wire from the diagram on the alarm to connect to any 12v constant and if the would work instead of the tach wire? Below is the part of the wiring diagram I am talking about. http://home.comcast.net/~antman1455/wiring1.jpg and here is the entire manual for the alarm/remote start: PerformanceTekniqueUserManual-ICBM7071 Any help is much appreciated. Thank you.

I wrote the "red wire" but meant "BLACK/ White" wire for a 12v constant. Anyone know how I can make this work?