the a/c button flashes yellow when i push it. i checked all my fuses, none blown.

when i was getting the car ready to go to the transmission shop, i noticed a rodent had chewed into the engine compartment wiring harness while it was sitting. i went looking because of misfires in two cylinders... i repaired the injector wires and found one more broken wire, colored red/white. i'm a bit impatient and the battery is hard to access... so i did repairs while the system was live. i know i shouldn't do this and i'm lucky my outcome wasn't worse given that i had no idea what wire i was patching at the time.

i grounded the red/white wire to the upper motor mount when i used it for leverage and the crimpers cut through the plastic on the butt connector (i heard the electric crackle). i hoped everything was fine, but i didn't try to use the a/c again until i picked the car up from the trans shop in 95 degree heat. before consulting my diagrams i checked for any more hidden damage, but found nothing. checking my diagrams i noticed that the red/white wire runs right to the hvac controls...



i'm guessing i fried my controls (? not sure how i did that by grounding a power supply *BEFORE* the unit, but i digress) ... i ordered a used replacement to test it out, but i should have read the repair process first. apparently i need a special scan tool to reprogram it according to my book. does anyone know if that special tool is a tech2? i've read that i can use a tech2 to possibly get codes from the hvac module, so i'm probably going to buy one anyway... but i wanted to know if it would get the job done as i kinda prefer the temp wheels on the replacement i purchased.

thanks in advance.