I have a 2006 PT cruiser - has the same issue: glitchy lock/unlock for a couple of months
then -0- start. I changed the button battery in the keyfob, but also called the mechanics
locally about it: the battery in the key is only there for the external activation of the car
locks. The actual ignition interlock communication w/ the car's computer is via a chip in
the keyfob. They wear over time. Solution: if you have a 2nd key, one that is less used,
try that. Otherwise, the dealership has to get you a new key, and then program it for your
car (pricey- like several hundred dollars, I heard).
The only other non-start issue I had was when I triggered the alarm lockout / kill switch. I
locked the car, then passenger exited. When I went back to move my car- zip. That is a
24 hour cycle, then it will work again. (or if you KNOW that is what happened, you use
your keyfob to lock/unlock the doors and let it know you are legit, and it's ok - but as I
didn't know that was what the problem was... I was skunked, and had the car towed in for
"repair" the next day it was fine (that 24 hour time period).
Best of luck. I hope you have a 2nd key. Shelley
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