manual key fob

My manual key fob (not the button key fob) will not go in to drivers lock but will go into passenger side door lock. But the key will start the engine. Is the black thing inside the key casing a battery of some sort which needs replacing & if so where can you buy a replacement

Hi erichart,

the black thing inside the key casing is the immobiliser chip (you won't start the engine without it) if you have a manual key fob its definitely
not a battery so you don't need one

If the key won't fit into the drivers door lock its probably jammed through lack of use.

Do you have a remote ( button ) fob to open the doors?

also I thought the C3s could only be opened manually via the drivers door
it should be the only door with a lock in it

Have been using manual key since C3 bought new so lock not jamming because of lack of use. Also there is a lock on both front doors and fob remote keys work also in both locks so it would indicate there is nothing wrong with the actual door lock itself

Hi erichart,

If the remote key works in the drivers lock then the manual key might have wear to the blade, check if both key blades have the same amount of wear, if they look exactly the same its possible the manual key blade is either further or shorter into the lock. I've had problems with wear
on these keys before.
I am still surprised you have locks to both front doors. one of the security features is that when locked only the drivers door can be unlocked with a key and the rest cannot be opened from inside or out because they're deadlocked.
does the manual key open and lock the central locking including locking the tailgate or do you need the remote fob to lock the car?

The manual key for the C3 locks all doors & tailgate with two turns of the key in either locks or using remote fob button twice. Car going in to garage soon so will get them to check out about length of blades (not a Citroen garage).