A Citroën C3 radio asks for its security code after the head unit loses its permanent live feed — a flat battery, a battery change, a jump start or the radio being unplugged. The code is held against the serial number of that head unit, not against the registration or VIN. Fitted units: Clarion RD3, RD4, RD45, touchscreen. Check the handbook wallet and service book for the code card. Once you have the serial, enter it in the radio code finder on this page.
Radio codes belong to the head unit serial number, not the vehicle registration or VIN.
A flat battery, battery replacement or radio removal is what triggers the code prompt.
Covers Citroën C3 2002 to present.
Bob's never displays a guessed or generated code — if a working code can't be retrieved you get a full refund.
2002 to present. Clarion RD3, RD4, RD45, touchscreen
How to find the serial number:
Check the handbook wallet and service book for the code card.
Unclip the trim surround around the unit.
Use extraction keys on single-DIN units or remove the four screws on double-DIN units.
Read the serial from the label, prefix letters included.
How to key the code in:
Presets 1 to 4 set the four digits.
Hold OK to submit on RD4 units.
The radio confirms and resumes.
Worth knowing:
2002–2009: Clarion RD3 units with a pull-out CD slot. Serial on the casing label.
2009–2016: RD4 or RD45 units, usually double-DIN behind a clipped surround.
2016 on: touchscreen systems, vehicle-coded rather than audio-code locked.
The C3 trim surround unclips by hand — take it off rather than levering on the radio fascia.
My C3 radio says CODE after a battery change That is expected on RD3 and RD4 units. Losing permanent live triggers the anti-theft lock and the code has to be re-entered.
Where is the C3 radio serial? On the label on the top or side of the head unit casing. Citroën units do not usually display it on screen.
Can I get the code from the registration? No. It is held against the head unit serial, not the vehicle.