The diaphragm on mine was leaking so I removed centre console ahead of surgery to replace.

It looks like an easy job if you drill a hole in the heater box and subsequently plug with rubber grommet. I'd got hold of the necessary rubber bungs ahead of this but before drilling wanted to try the less invasive method of removing glovebox and taking off the air hose to passenger door air outlet and going in through the air outlet.

Couldn't see a thing with a mirror but I got hold of a wifi inspection camera (very cheap as your phone/tablet provides the screen) and it took seconds to twist off the actuator arm, and reattach with the new diaphragm installed using a long 1/4" extension and 9mm socket to push the arm onto the comb flap lever clip. All viewed in comfort on phone screen sitting in passenger seat!

Photos show the arm in position ready to be pushed on, and the attached arm

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