I had a 2005 CRV and had a similar problem. the door wouldn't lock with the key or the remote. It turns out that the sensor for the tailgate was bent a little so when the gate was closed it would tell the car that something was not closed. funnything is that the gate light wasn't on. I just bent it back so that the gate sensor would actually tell the gate was closed and i was finally able to lock the doors with the key and the remote. may be something is not closing right? i was able to lock the doors from the pasenger door when inside the car but now from outside. I hope that helps.