54 C3 1.4HDI Resynch remote fob

[MikeT]

Following the success of fixing the central locking viewtopic.php?f=3&t=60700#p583062
I thought I'd see if I could resynch the second fob I was given but I'm not having much luck.
Both keys operate the locks and ignition and starts the car but only the first fob will operate remotely.

According to the handbook, after replacing a fob battery, I should unlock the drivers door and open it, then press the remote button.
Well, that didn't work and I would have been gobsmacked if it did to be honest.

A different (online) method says to turn on ignition, press button for 10s, turn off ignition. Wait 1min. Get out, close door, then try remote.
Nope, that doesn't work either.

Checked all I could - swapped batteries, original remote still works (thankfully!), inspected pcb with jewellers loupe, got battery voltage at micro-switches, even pick up 433mhz signal on radio scanner when buttons are pressed, so I'm pretty sure it's the re-synch procedure I've got wrong.

Any further suggestions before I get Lexia on the case?

[GiveMeABreak]

You did the correct procedure Mike (official routine below).

• Put the HF key to be synchronised in position "ignition +"
• Within the next 10 seconds, press one of the HF key buttons
• Release the HF key button

The type of key issued for that year was this:

So if you have another type of fob it probably won't work as it will be the wrong version for the remote functions.

[MikeT]

You did the correct procedure Mike (official routine below).

• Put the HF key to be synchronised in position "ignition +"
• Within the next 10 seconds, press one of the HF key buttons
• Release the HF key button

The type of key issued for that year was this:
Mike C3 Key.PNG

So if you have another type of fob it probably won't work as it will be the wrong version for the remote functions.

Yup, that's the same design of both synched and non-synched remote Marc. PCB's are identical too. Even the audible signal I hear through the 433.nnn frequencies sounds identical.

[GiveMeABreak]

Ok, so nothing left but to pair BOTH the keys again using Lexia - as long as you have the confidential code of course

[MikeT]

I'll have to get the code off the stealers but there is a Lexia HF signal test I can try.

[Oktopod19]

Hello I'm new here.
Please if somebody can help me I have problem whit new key fob for Citroen c3 year 2010.
The problem is next:
The original key fob remote transmitters was lost, and from car I have storage key whiteout buttons for lock and unlock.
I take new key remote whit plate completely whit id chip - transponder.
I cut and made programing to car after the key started engine and working normal.

I have problem whit remote control of central locking.
From car button for auto lock the central locking work normal and whit mecanical using of key to door.

I try procedure whit pressing 10 seconds button open-closed the door but not succeed.
Please if somebody have experience whit same problem to help me or every idea is welcome for me in this position.
Thanks advance

[GiveMeABreak]

Hi

Your problem is because although you have coded the new transponder chip to the car in order to Start it, you won’t have the correct electronics in the key fob to operate the central locking.

This is separate circuitry and needs to be the correct type to work with the car. So in other words the circuitry in the replacement fob is not compatible with the vehicle for the remote feature.

[Oktopod19]

Thanks very much for this information.I suppose the same, really is important to share thinking whit else people.
I will inform you do is this reason after trying whit another remote.

[GiveMeABreak]

Just a thought - when you tried to synchronise the remote controls after programming them, it is important NOT to press any buttons on the fob for at least a minute before resynchronising them:

• So you should wait a few minutes do not press any buttons on the fob.
• The put the key in the ignition and switch the ignition on only - not the engine.
• Then press the lock button on the fob for 5 seconds (within a 10 second period).
• Turn off the ignition
• Repeat for the second key.
• Try the remote locking function.

That is how you synchronise the remote fobs. But if this still does not work, then what I said in my earlier post probably still applies - you may not have the correct circuitry in the fob - so it is sending the code on a different frequency.