code alarm ca645 on 94 grand cherokee

yeah your 7 flashes means the tach is not programed correctly.    

Tach program:

turn key on, press valet button 3 times, turn key off.

Press and hold valet button as you start the car.   The parking lights should flash indicating the brain learned tach.   I would hold the valet button down for atleast 10 seconds just to make sure. 

It is deffinitly a tach issue.   You may have to repeat those steps a few times for it to learn.   But it should be all set

Well it sounds like the brain is in lock mode.   Or atleast thats what I call it.   You will probably have to pull the fuses on your 12v wires and then re-install them.   This resets the unit and should take care of your inhibit problem.     But before you do that check your hood pin.   3 flashes can also mean that you have a bad hoodpin.   Check that first then go with the fuse route.  

As far as the trunk pin.   I dont think your vehicle has a seperate trunk pin.  So I am guessing that maybe you used the wrong wire for your doorpin.    I think that vehicle has - door triggers and if that is correct you should of used the (green - door trigger input wire)        Otherwise check to see if the Blue/White wire is hooked up or grounding out somewhere.   That I believe is the trunk pin wire.   Its labeled as an instant - trigger and is commonly used for trunk pins.    

We used to do that on occasion at work, until they start coming back on a regular basis. Every one of them would flash 3 times on an R/S attempt, and wouldn't allow us into programming mode to reprogram tach. The whole brain had to be unplugged and reset. and tach had to be run. I don't know how the new 425A brains handle it, but the older 425's couldn't be run without tach.