IWC Schaffhausen AQUATIMER AUTOMATIC 2000 Mode D'emploi page 24

Setting the time
Pull the crown to position 2. This will stop the movement.
To ensure that the set time is accurate to the second, it
is best to stop the movement as the seconds hand reaches
60. You can now position the minute hand exactly on
the minute line. To start the seconds hand, push the crown
back to position 0. When setting the time, please be
aware that the date change always takes place at midnight
(24.00 h). If this change has already taken place at
12 noon, you must move the hands forwards by 12 hours.
Important: Although the watch is water-resistant in
positions 0, 1 and 2, the crown must nevertheless always
be screwed down again for normal use (position X).
Reading the time in the dark
The dial, the hour and minute hands as well as the
marking on the rotating inner bezel of your watch are
provided with luminous elements which permit the time
to be read without problem, even in total darkness.
The luminous point at 12.00 serves as a reference point.