C3 key not recognised

[aerodynamica]

Hi all, I was helping someone who's C3 wouldn't unlock and given the minus temp was not ideal.

I thought the remote battery just was flat and I suggested there is a hidden key in the remote - and there was- to open the door. I did suggest thinking about the next move because the alarm would likely go off and I noted it was a 'keyless' situation. Unlike my c5x7 and even my dad's previous Picasso that had a slot in the dashboard for the remote. Anyway, open door with key, alarm goes off as expected, and then the display shows "key not recognised"... no response to pressing start or any other. I looked and couldn't see any slot anywhere so it must be one of those 'in the handbag' keys. (I'm still old skool of course)

Anyway, after a few rounds of the alarm in the cold and dark that the neighbours must've also enjoyed, the car suddenly starts!

I suggested she doesn't stop until she is done for the day! Anyway, not my car like I say (Estate agent) but apparently it repeated the behaviour next day.

Is this a case of simply needing a battery? I couldn't see any easy way to open that remote. I thought these keyless remotes used some type of RFID tag and those don't require power from a battery so far as I know..

[GiveMeABreak]

If the vehicle has a keyless entry and start, then on the left side of the steering column there is a flat part which is where the fob needs to be placed to switch the alarm off. This is the backup release for the electronic steering lock and immobiliser if the fob is not detected and allows the car to be started:

From the manual....

Back-up starting
A back-up reader is fitted to the steering column so that the engine can be started if the system does not detect the key in the recognition zone, or if the battery in the electronic key is flat.

? Place and hold the remote control against the reader.
? With a manual gearbox, place the gear lever in neutral then fully depress the clutch pedal.
? With an automatic gearbox, select mode P, then fully depress the brake pedal.
? Press the “START/STOP” button. The engine starts

Back-up switch-off
If the electronic key is not detected or is no longer in the recognition zone, a message appears in the instrument panel when closing a door or trying to switch off the engine.
? To confirm the instruction to switch off the engine, press the "START/STOP" button for approximately 5 seconds.
In the event of a fault with the electronic key, contact a CITROËN dealer or a qualified workshop.

[aerodynamica]

Ah! You'd think she would have known this having owned the car nearly 4 years.... o well

[GiveMeABreak]