how do you reprogramme a 1998 Renault scenic key fob

It depends on which type of key u have as they changed in 1998.
If ur is the type where u rely on the remote locking to deactivate the immobiliser u can reprogramme the key ur self using a four digit security code.
You can get the code from ur renault dealer, they r allowed to charge u a fee for it if they wish, & they may ask u to prove u own the vehicle.
You enter the code using the central locking button in the car.
You simply make sure the immobiliser is active, then with the ignition switched on u carry out the following.
Press the central locking button down (it does not matter which side of the switch u press)
The immobiliser light will start to flash at a slower rate.
Count the flashes until u have counted enough flashes to match the first digit of the code.
Release the button & then press it again & count he number of flashes required for the second digit of the code.
Repeat this for all four digits.
Once all four have been entered the immobiliser light should illuminate steadily for a few seconds & then go out.
(If it flashes then the code is incorrect or incorrectly entered).

Then switch off the ignition. Press & hold the central locking button, keep it pressed until the central locking operates ( the doors lock & unlock in one cycle)
You have 30 seconds to now point the plip key(s) at the receiver in the roof & press the key fob three times (each key) If the key is sucessfully programmed the doors will lock/unlock on the third press.

It the key fob is the transponder type, u cannot code a key yourself. You can resyncronise it though. With ignition off, press & hold the key fob button, after about 10 seconds the light on the key will stop flashing, press the key fob button three times & if the key will resyncronise it will at this point operate the locking system.

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