Clutch Start Switch

WARNING: This page is about a different car, the 2013 Subaru Forester. However, it is still accessible from the selected car via links, so may be relevant.

Fully depress the clutch pedal and hold it.
Install the clutch pedal plate and clutch switch so that the gap between them is 2.0 - 2.5 mm (0.08 - 0.10 in), and then tighten the lock nut.
Tightening torque:

8 N.m (0.8 kgf-m, 5.9 ft-lb)

Fig 1: Identifying Gap Between Clutch Pedal Plate And Clutch Switch
Courtesy of SUBARU OF AMERICA, INC.
Connect the clutch switch connector.
Make sure that engine does not start with clutch pedal not depressed.
Make sure that engine starts with clutch pedal fully depressed.