Hi

I would start by replacing the battery, if this dosent work, then try reprogramming the key to the car, the process is as follows.

1. Turn Ignition OFF.
2. Press the central door locking button for more than 5 seconds. Note :
the door should lock then unlock.
3. When this happens, 15 seconds is allowed and the immobiliser warning
light illuminates.
4. Point the 1st key at the receiver and press the button once, the doors
should lock and unlock.
5. Point the 2nd key at the receiver and press the button once, the doors
should lock and unlock.
6. Check the remote control unlocks and locks the doors


If this dosent work, if it is the infa red type, then it is probably the sennsor, which is easily changed, and you may be able to get one from the breakers yard.

If you have the radio type, then you will need to have the car plugged into an OBD2 diagnostic reader to identify and possibly rectify the fault.

Hope this helps

Trev