Remove the door trim (see Removing the door trim)
Disconnect the lock release rod from the lock release roller.
Usually the outer handle is removed to replace the lock cylinder or when repairing the door.
Before unscrewing the handle, it is advisable to moisten the threads of the nuts securing the handle with penetrating lubricant VD-40 or simply kerosene.
And wait a little while the lubricant penetrates the threaded part.
Often, when unscrewing the handles, the pin breaks off due to oxidation.
Use an 8-point socket to unscrew the two nuts securing the door lock
Remove the outer door handle along with the rod.
Use a drift with a diameter of 1.5 mm to knock out the pin
Remove the lock leash.
Pry it up with a screwdriver
Remove the cylinder spring.
Take out the larva
Replace the cylinder with a new one, lubricate it on the outside with grease and install the handle in the reverse order