Remote central locking was introduced as an option on Mk2 ax's. The system uses an infra red key fob and a receiver mounted in the roof console, near the courtesy light.
The same IR RCL system was used on the following models and is interchangeable with the Ax system.
Ax's came with this type:
Saxo's came with this type:
The ax and saxo receivers are transferrable and use the same loom connector. Note the saxo receiver is has an extra 'receiver' element, to give it better range. Also the saxo key fob has the citroen badge on the button and is more modern looking with a slightly updated key fob, but inner workings are the same.
Grey: Ax Black: Saxo
If you look on the back of the PCB on both the remote and the receiver, there is a yellow sticker with a code on it. Obviously, both codes need to match for the system to work.
You can NOT programme InfraRed plips. The dealer may be able to help if you have the code on the yellow sticker, but you may have to buy a new transmitter or receiver.
IR Receiver sits behind the red 'dome' by the courtesy light.
Remove courtesy light and undo two phillips screws. Remove the housing to get access to the receiver.
Replace the receiver with new working one and put back together!
Job done, remote central locking!!
The down side of IR remotes s that the receiver needs a clear line of sight to the fob, rather than modern systems that use 'radio' frequencies.
The IR key fob is based on the Philips TEA5500 chip. The code is hard-coded to the PCB which is why they cannot be re coded, i believe.
Part No’s (Ax Kit)