1999 Chevy Tahoe remote start

let me make sure i have it correct......the WHITE/ red wire that says to go to the "tach input" is the one that i connect to the white wire that goes into the black harness that is pluged into the(WHITE side of the  ECM ) .

Next my question is about the yellow wire from the (4-wire harnessfrom the alarm brain) it is the "(-) neg. ignition out" it shows that i should hook it up to the "85" spot on the "ignition 2 relay" ................and ..........on the pass II it has a yellow 22 gauge wire that says to go to the " ignition #2 on remote start................................so do i connect that to the ignition 2 relay and if so at what spot on the relay.

Also i am not going to use the accessories on the unit so do i still need to hook up the GRAY wire that comes off of the high current harness (6 - pin).

Thank you so much for all of your time this is very generous of you and you have earned a future customer.

Thanks for the fast replies!!!   if i leave the heater/AC in the on position then wont it come on when the truck starts.(thats what i was thinking).  & Great i will go do that to the ignition right now.

Thanks 

what do i do with the Yellow "(-) neg ignition out"(4-pin wire harness) that says to go to the ignition 2 relay ...........do i go to the white ignition wire with it also. 

No you will not need to use that wire anymore because the bypass module has an ignition 2 wire already so you don't need to have double the trigger on the single wire. The YELLOW wire is only used if you did not have the bypass module 2nd ignition.

As far as the ACCESSORY wire goes, you should wire it up and if you don't want the fan engaged then leave the fan off, but when you do want it on ( but you don't have the wire hooked up ) then it get hot in the truck ( or cold if your in Canada like us )

ok so do i have the WHITE/ red wire correct

yea