Wiper Does Not Park

[malagabob]

The rear wiper on my trusty old bus, ( Mk1 Focus ) does not return to the park position when using the single wipe function . I have checked the tightness of the nut and that is OK.

[TWR]

Has the wiper Arm been removed? has it been put back in the same area? If no to the Latter, possible Spline on wiper worn, take off the arm & check, if worn use a very fine file.

[bhg481]

In the good old days, when God was still a lad, wipers didn't self-park. When you turned them off, they stopped so, to avoid having them block your view when off, you had to switch them off when they were out of the way.
Then the self-parking wiper was invented. As the wiper motor starts to turn it operates a switch which connects power to itself, thus keeping the motor running even if the wiper switch is turned off. When the wiper arm is in a tidy position this connection is broken. If the wipers are still switched on the motor continues to run, otherwise it switched off.
The chances are that this connection is not being made on your car, probably due to either water ingress or a bad connection somewhere. If you can get to the wiper motor have a good look at the connections on it. Otherwise try to open up the motor and look at internal connections.