Originally Posted by Hojekang
As you know, when I pressed #1 once , the door was unlocked. And, when I pressed the same button again, then the door was locked. However it doens' t work any longer.
The switch box is lightening when I press the button and the anti-theft alarm works fine when I press #4 button.
Which part do I have to check first?.
If at least one button on your remote works, but others do not, I would try cleaning the remote itself. Do you have a second remote to compare it with?
In other words, if at least one button on your remote works, then the car can "hear" you and it recognizes the remote that'* talking to it. Therefore you need to check whether the dead buttons are actually transmitting something. It sounds like they are not.
If you carefully take it apart, you should be able to separate the buttons (probably a molded rubber sheet) from the circuit board. Clean any contact surfaces you find with alcohol, reassemble, put in a fresh battery and try again.