Door locks wont unlock other doors.

[gapboi210]

I think I have an aftermarket alarm/keyless entry. The key has a remote attached on the key but it does nothing. I have 2 other remotes and they lock and unlock and so on. However most of the time when I press the unlock button twice on the remote, it wont unlock the other doors. If i try pushing the button on the door inside the car the unlock switch does not respond. However, the locking portion of the switch does work. Any ideas? I might try to take it to an alarm place but I have a feeling they are going to suggest a whole new system for a low low price........