2005 C4 key replacement

This is the Forum for all your Citroen Technical Questions, Problems or Advice.

Moderator: RichardW

tomaskriv
Posts: 77
Joined: 21 Oct 2019, 19:31
Location: Ireland
My Cars: 2014 Citroen C4 Grand Picasso
x 3

Re: 2005 C4 key replacement

Post by tomaskriv »

Thanks for explaining me this. So in our case mobile locksmith replaced transponder. Well added new one because now the original key starts the car only with added transponder. But then WHY it is not locking/unlocking the doors if same key was able to d othis even when the transponder was damaged and key was unable to start the car. After the locksmith added transponder end reprogrammed the key, locking function was lost and he was scratching his head without any logical explantaion...
tomaskriv
Posts: 77
Joined: 21 Oct 2019, 19:31
Location: Ireland
My Cars: 2014 Citroen C4 Grand Picasso
x 3

Re: 2005 C4 key replacement

Post by tomaskriv »

User avatar
GiveMeABreak
Forum Admin Team
Posts: 37005
Joined: 15 Sep 2015, 19:38
Location: West Wales
My Cars: C3 Aircross SUV HDi Flair Peperoncino Red (The Chili Hornet)
C5 X7 2.0 HDi Exclusive Mativoire Beige (The Golden Hornet)
C3 1.6 HDi Exclusive Aluminium Grey (The Silver Hornet)
C5 MK II 2.0 HDi Exclusive Obsidian Black
C5 MK I 2.0 HDi SX Wicked Red
Xantia S2 2.0 HDi SX Hermes Red
C15 Romahome White
XM 2.0 Turbo Prestige Emerald Green Pearlescent
XM 2.0 Turbo Prestige Polar White
XM 2.0 SX Polar White
CX 20 Polar White
GS 1220 Geranium Red
CX 2.4 Prestige C-Matic Nevada Beige
GS 1000 Cedreat Yellow
x 5646

Re: 2005 C4 key replacement

Post by GiveMeABreak »

As I mentioned - it really does depend on the type of system you have - they can differ slightly - so as you can see on some the electronics send out different codes depending on the function - and as long as the fob is authorised (programmed) the remote functions should work.

The coded message sent to the receiver (in the car) by each remote control is composed of the following codes:
  • A fixed code linked to the key
  • A rolling code matched with the vehicle’s receiver
  • A code corresponding to the action to be performed
  • A code corresponding to the condition of charge of the batteries
Please Don't PM Me For Technical Help

Marc
User avatar
Paul-R
Donor 2023
Posts: 6916
Joined: 07 May 2009, 16:24
Location: Wirral, NW England; Vaucluse 84, France
Lexia Available: Yes
My Cars: 2015 1.6 Blue HDi 120 Peugeot 308 Active SW
2013 2.0 HDi 163 C5 Exclusive Tourer
2003 2.0 HDi 110 C5 Exclusive Estate (Gone)
2001 2.0 HDi 90 Xsara Estate (Gone)
x 1369

Re: 2005 C4 key replacement

Post by Paul-R »

As long as the new key will start the car then I would try resynching again.
As I get older I think a lot about the hereafter - I go into a room and then wonder what I'm here after.

Inside every old person is a young person wondering what the hell happened.

"Trying is the first step towards failure" ~ Homer J Simpson​
tomaskriv
Posts: 77
Joined: 21 Oct 2019, 19:31
Location: Ireland
My Cars: 2014 Citroen C4 Grand Picasso
x 3

Re: 2005 C4 key replacement

Post by tomaskriv »

This is all we can do for now.
tomaskriv
Posts: 77
Joined: 21 Oct 2019, 19:31
Location: Ireland
My Cars: 2014 Citroen C4 Grand Picasso
x 3

Re: 2005 C4 key replacement

Post by tomaskriv »

Hi Marc
Can you tell donwe need ASK or FSK key?

Thank you.
User avatar
Paul-R
Donor 2023
Posts: 6916
Joined: 07 May 2009, 16:24
Location: Wirral, NW England; Vaucluse 84, France
Lexia Available: Yes
My Cars: 2015 1.6 Blue HDi 120 Peugeot 308 Active SW
2013 2.0 HDi 163 C5 Exclusive Tourer
2003 2.0 HDi 110 C5 Exclusive Estate (Gone)
2001 2.0 HDi 90 Xsara Estate (Gone)
x 1369

Re: 2005 C4 key replacement

Post by Paul-R »

If it's the same as the one I bought for our 2013 X7 it'll be ASK.
As I get older I think a lot about the hereafter - I go into a room and then wonder what I'm here after.

Inside every old person is a young person wondering what the hell happened.

"Trying is the first step towards failure" ~ Homer J Simpson​
Post Reply