Car Alarms: checkmate car alarm jt3kt6b, connector port, generic info

Question
the remote performs 3 functions lock unlock doors and reset ignition. 2days ago doors stopped unlocking remote just repeats other 2 functions. please help if you can. also wondering how difficult to replace

Answer
I have nothing on Checkmate alarms so it'll
be generic info, but you would need to inspect
all connections, specifically the door lock
connectors for validity.

Can't think of a reason the locks would not
operate, but it WILL still arm and disarm, other
then the connector port is bad or connectors
are mis done.

Are you able to go into and out of programming/
valet-overide mode?

ALARMTEK