Fresh Air Enters Passenger Compartment

COMPLAINT:
With button "e" (off) pushed, fresh air enters passenger compartment






Cause/Remedy:
a) Switchover valve (16 or 17) damaged.
Check switchover valve (16 and 17) and replace, if required. Check electric activation of electromagnetic switchover valve and fix.
b) Pushbutton switch damaged.
Renew control unit.