Hello everyone!

 

I am new here and I apologize in advance if this particular issue was mentioned or covered already.

 

The central locking on my Fabia works fine, well except for a small quirk.

 

The passenger side door locks all doors, but the driver side doors lock all doors except the passenger side.

 

This has led to many times I've forgotten to lock the passenger side, what could this possibly cause?

 

I've seen many cases where the central locking is completely dead (or only on one side) but never like this.

Check for broken wires inside the rubber door bellows as it's a common issue. If it's not that it could be the door lock unit inside the door. They can suffer with dry solder joints or microswitch failure.

May also be the motor inside the passenger side lock unit. When you unlock the car with the key in that door, it doesn't need to do anything.  When you unlock from the other side it does need to work. 

It's not very easy to get into, but on a Polo of mine, cleaning the commutator brought this one back to working properly.