If you are having a remote car starter problem – that is, the car does not start with your remote fob, most likely your remote battery is weak or gone. Replace your remote battery and try.
I had a same issue. I took it to mechanic and no body could troubleshoot. I decided to replace the remote starter battery and it worked.
I recommend that you change your remote starter (Key fob) battery every year.
Here are the reference data from remote car starter.