The following are easy to recognise on the cutaway model:

• Armature with carbon brushes
• Field (comprising permanent magnets)
• Worm on the armature shaft
• Worm gear of nylon of the wiper shaft
• Strip conductors for limit switching

Functions:

• Allow the motor to run by pushing the button
• Limit switching when the button is let go of
• Current measurement in idling and under load