Hello, I have just picked up a 2003 Civic LX 4dr. The lock switch on the drivers door will lock all 4 doors, but it won't unlock any of the doors. The car has remote fobs, but I believe this was an after market modification. The remote will lock and unlock all the doors with no issue. You can manually move the door locks open and lock with no issues, they move freely. I have replaced the switch on the drivers door thinking this was the likely culprit, but this did not resolve the issue. The previous owner mentioned that he just had the window motor and another part replaced in the drivers side door as the window was stuck open. The window works fine, but wasn't sure if that could indicate anything.

I have been searching through numerous posts trying to find an issue like this, but unsuccessful. Just hoping to get some pointers on what to check next.

Thanks