Aftermarket Berlingo Keyfob transponder problem

[rorova5]

Good evening all,

I paired spare key with diagbox so now have original and aliexpress key. Both keys start van fine and then I resynced the central locking. 

After I use the chinese transponder for central locking the van no longer unlocks and locks with this key and my original fob. It only works sometimes but still starts the van. Changed both fobs batteries. After I resync key with original it works again but if i resync with the chinese one too and use it, it will work twice then stops working. Does anyone know why? 

I bought key with FSK modulation Number of Buttons: Pcf7961 ce0536

[Stoots1975]

Good evening all,

I paired spare key with diagbox so now have original and aliexpress key. Both keys start van fine and then I resynced the central locking. 

After I use the chinese transponder for central locking the van no longer unlocks and locks with this key and my original fob. It only works sometimes but still starts the van. Changed both fobs batteries. After I resync key with original it works again but if i resync with the chinese one too and use it, it will work twice then stops working. Does anyone know why? 

I bought key with FSK modulation Number of Buttons: Pcf7961 ce0536

You're lucky your aliexpress  key fob worked at all, mine didnt

[rorova5]

Damn, so whats the alternatives for a replacement transponder chip?

[Tikki]

I have been using the Xhorse FOB Keys on many B9 and non problem with those. you can program with diagbox, lexia or other key program software

[rorova5]

Good evening all,

I paired spare key with diagbox so now have original and aliexpress key. Both keys start van fine and then I resynced the central locking. 

After I use the chinese transponder for central locking the van no longer unlocks and locks with this key and my original fob. It only works sometimes but still starts the van. Changed both fobs batteries. After I resync key with original it works again but if i resync with the chinese one too and use it, it will work twice then stops working. Does anyone know why? 

I bought key with FSK modulation Number of Buttons: Pcf7961 ce0536

You're lucky your aliexpress  key fob worked at all, mine didnt

I have been using the Xhorse FOB Keys on many B9 and non problem with those. you can program with diagbox, lexia or other key program software

thanks. Have you got a link? Tried searching but couldn't come up with anything. Did you get an fsk fob? I assume my immobiliser chip is correct but something it happening with the central locking. Perhaps its sending incorrect information, corrupting the data.

[Sol]

The central locking and the engine immobilizer are completely different systems and not related although both are operated by the key.

The transponder chip is for the immobilizer, non powered and needs no battery. It's code is always the same.

The central locking uses the battery powered transmitter in the key and has a rolling code that changes each time you lock. When locked, the car tells the key what the next unlock code is but remembers the last few codes used in case you swap keys. (So that the other key can also open the doors again after not being used for a while.)

Maybe the Chinese key can't hold more than two rolling codes so it stops opening the doors after that.

Also if you cloned the original key...then you have two keys that look like the same key, to the car. But one key then responds with a different rolling code from the last one the car gave to "the key" - does this make sense.

Keep one as an emergency spare which works and stop swapping them around.

Xhorse are on OBD.com and AliExpress if you search the brand in Google. Personally I wouldn't trust a Chinese key as far as I could fling it. Quality control is non existent so it's a lottery whether you get a good item or a dud.

[shtu]

I recently bought some replacement key shells, of the usual chinese quality. The battery contact in the shell was made of absolute monkey metal, far thinner and more flexible than the original citroen ones. The remote locking worked maybe 50% of the time.

The fix in my case was to swap the terminal across from the old case.

Might be having the same issue with your replacements?

[rorova5]

The central locking and the engine immobilizer are completely different systems and not related although both are operated by the key.

The transponder chip is for the immobilizer, non powered and needs no battery. It's code is always the same.

The central locking uses the battery powered transmitter in the key and has a rolling code that changes each time you lock. When locked, the car tells the key what the next unlock code is but remembers the last few codes used in case you swap keys. (So that the other key can also open the doors again after not being used for a while.)

Maybe the Chinese key can't hold more than two rolling codes so it stops opening the doors after that.

Also if you cloned the original key...then you have two keys that look like the same key, to the car. But one key then responds with a different rolling code from the last one the car gave to "the key" - does this make sense.

Keep one as an emergency spare which works and stop swapping them around.

Xhorse are on OBD.com and AliExpress if you search the brand in Google. Personally I wouldn't trust a Chinese key as far as I could fling it. Quality control is non existent so it's a lottery whether you get a good item or a dud.

I knew about the first part but not the rolling codes. Interesting insight, thanks.

Why do you think my original key stops opening the car after the Chinese key first fails to work? Because it should work as you said the car remembers the last few codes..The two keys are distinguishable I used different cases.

Regarding the last part, whats a reliable alternative for me to use diagbox for a spare that doesnt involve the dealer, if any? The xhorse keys are just generic shapes, nothing that matches citroen keys that I can see.

I recently bought some replacement key shells, of the usual chinese quality. The battery contact in the shell was made of absolute monkey metal, far thinner and more flexible than the original citroen ones. The remote locking worked maybe 50% of the time.

The fix in my case was to swap the terminal across from the old case.

Might be having the same issue with your replacements?

This could be it. I do have a spare fob from a different Berlingo that I can try solder the battery terminal to the Chinese chip.

[shtu]

In my case I didn't need to do any soldering - the terminal was clipped to the plastic case.

[rorova5]

In my case I didn't need to do any soldering - the terminal was clipped to the plastic case.

Ah different style key fob then. I have the CE0523 type fob.