Finalement j'ai trouvé la solution, mais avant tout je vous raconte une petite anecdote. Je suis allé chez Citroën, ils ont vérifié les lumières visuellement, puis aucun problème, il faut prendre un rendez-vous avec nous pour pouvoir connecter la voiture avec la valise, et ... le coût entre 80 et 130 euros ! cela ne confirme pas la résolution de mon problème.
Après une longue recherche, je suis tombé sur un forum dans lequel il y a la procédure exacte pour reset Bsi pour les voitures récentes du PSA. Voici le lien :
https://frenchcarforum.co.uk/forum/v...ic.php?t=61997
j'ai copié coller le contenu au cas ou, il est en anglais.
Procedure:
Open bonnet and driver's side window (the window is left open for emergency access reasons only whilst battery is disconnected).
Ensure all doors are 
and remove key from the ignition (do not leave the key in the ignition as the transponder circuit will detect the key and this can prevent the networks from sleeping).
For C5 X7 Tourer V6 Engines, with / without motorised tailgate or vehicles where the battery is in the rear boot:
Open the boot
Disengage the motorised function (short manual action down then up)
Mechanically lock the lock using a tool (which results in the boot light switching off)
If disengagement is not possible, close and open the boot electrically. Re-open the boot lock mechanically. Repeat the procedure for disengaging the motorised function of the boot above.
This will fool the BSI into thinking the tailgate is . Then follow the procedure from shutting all the doors - but now you can leave the tailgate open.
It is essential though, that after refitting the battery, that you remember to flip the tailgate locking catch back over to the unlocked position.
Procedure continues for all vehicles:
Wait for 5 minutes, - Don't press any buttons, open any doors or use the remote key fob during this time.
Disconnect the vehicle battery negative lead and do NOT let it reattach or touch the battery negative terminal post again (use some cloth or other non-conductive material as a barrier). If it touches, the whole process needs to be repeated as you have effectively started the wake up procedure if it touches the terminal.
A) If applicable, now undertake any work or operations you are planning that needs the battery disconnected, OR:
B) If just resetting the BSI, wait 5 minutes whilst the negative terminal is disconnected.
Reconnection:
Ensure all doors and tailgate are shut (if you have been doing any work on the car).
For Keyless Ignition / Stop Start Vehicles only: For these systems, when reconnecting the battery, ensure the fob is not within 2-3 metres of the car perimeter until the time of reconnecting the battery has lapsed.
Reconnect the vehicle battery.
Wait a further 3 minutes (do not open doors).
Switch on the side lights through the driver's window.
For standard vehicles, switch on the ignition only with the key, don’t start vehicle yet and check ignition lights come on.
For Keyless Ignition / Stop Start Vehicles only: With the Fob in the car or in the Fob Reader, press the Start Stop button without pressing any pedals. That will switch the ignition on only.
For standard vehicles, with the key still in the ignition and within 10 seconds of switching the ignition on, hold lock button on key fob down for a few seconds (to synchronise the remote fob).
Switch off ignition, remove key through window, then operate Central locking several times.
For Keyless Ignition / Stop Start Vehicles only: Press the Start Stop button again, without touching any pedals to switch the ignition off.
Remove the Keyless fob from the reader through the window, then lock the car using the sensor on the door handle or the button on the fob. Now unlock the car either using the sensor on the door handle or the fob.
Now open door, start the engine and check there are no errors etc.
Switch off your side lights
Après avoir fini la procédure, aucun voyant n'est allumé, et tout est rentré dans l'ordre. Même les défauts sont disparus de mon application Mycitroen.
Merci à vous pour vos réponses.
J’espère que cette méthode aidera tout le monde !
A+