viper 5500 remote start. 99 explorer with pats system

remote wont respond to start button, it just transmits but wont recieve.
however the door locks work fine, transmits and recieves.

broke out the meter, power is fine, no blown fuses. everything hooked up fine, good ground.

wont even attempt to start, thats all i want it to do, then i can bypass the pats if i can even get it to attempt to start.

can anyone help me?
is it a bad product?

i have the car apart and the brain is dangling from the dash now, im mecp certified, but i havent a clue what to do, as i havent installed in a few yrs.


tia

is there a ground to start wire to test the brain?

no not that i know of.
im probly gonna pull the viper out of my 4runner an test it in the explorer

does the explorer have a second starter wire? if so you may have to use a relay to activate it.