Central Locking Issue code 46 & 47

[tdamlo]

I have been having an on going issue with my central locking system. My passenger door doesn't seem to synchronize with my fuel door and drivers side door. All my door handle micro switches operate as they should. This would point to the passenger side door lock, but when you exit the car from the passenger side it doesn't trigger the alarm fault with 2 chirps from the alarm horn. When you exit the drivers side of the car the alarm does chirp twice indicating a fault.

The durametric codes read

code 47 central locking synchronization

present
frequency: 127

code 46 central locking synchronization

present
frequency:1

Do either of these codes point to drivers side or passengers side?

I did check the CLU under the drivers seat for moisture damage and corrosion and it looks brand new.

Looking for a place to start. Replace both locks?

My car is a 97 with the optional m535 alarm