sometimes when I try to lock the doors by pressing on a little black button on a door handle I get one long beep and the doors won't lock. What causes that?
A door might not be fully closed. The hatch might not be fully closed. You might not be giving it a second between closing and locking. You might have a finger between the door pull and door, which is then giving mixed signals of lock and unlock at the same time.
It will also happen if a fob is still in the car; could be a second fob in a jacket or purse or one accidently left inside the car. This is a good thing.
Sometimes when we go someplaces, my wife likes to hide and leave her purse in the car, but she keeps forgetting to take out her FOB out of her purse. The long beep tells us this every time. Then I end up carrying both FOB's with both all my keys and hers, and thats a lot of keys!
Actually, I've found that I can push the button while closing the door (basically pushing the door closed with the button), and it will lock a moment after closing is completed. Also, I don't think you can sent it mixed signals, but I will have to try it today, just to see. It should make for an interesting experiment. I will try it out. I just turn of the SE/SS and let her hide the purse in the car, it's easier than digging for keys.
On a somewhat similar note... I usually have the FOB in my pocket while driving. Sometimes, though, I'll place it in the cup holder or on the passenger's seat. Whenever I exit the car when the FOB has stayed in my pocket, the doors lock without any problem via the door knob button. Yet when I exit if the FOB has been on the passenger's seat (or in cup holder), of course taking it with me outside the car and closing the door properly, the door handle button does not respond, not a quick beep to lock, or even the long tone to warn. Nor does the lock button itself on the FOB cause the car to lock. I finally found that holding the black button on door handle for at least 10-15 seconds will lock the car eventually! What could I be doing wrong here? Only pattern I've discovered is where I'm carrying the FOB while driving. Always holding in my hands after exiting car.