Subaru LEGACY 2002 Quick Reference Index page 512

HVAC System (Heater, Ventilator and A/C)
C: ACCELERATION CUT SYSTEM
The A/C switch turns the air conditioning system ON and OFF. The on-off signals from the switch
are transmitted to the engine control module (ECM).
When the ECM receives a full-throttle signal from the throttle sensor during compressor operation,
it deactivates the A/C relay to interrupt electric current to the compressor magnet clutch. This pre-
vents the degradation of acceleration performance. The A/C relay is in the main fuse box located
on the left side of the engine compartment.
D: IDLE SPEED CONTROL
The idle air control solenoid valve increases the engine idling speed when the compressor is in
operation.
The engine control module activates the idle air control solenoid valve when it receives an A/C
switch ON signal so that necessary by-pass air is introduced into the throttle body to ensure proper
idling speed for an increased engine load.
COMPRESSOR CONTROL SYSTEM
AC-40
Pressure sw
Idle air control
solenoid valve
B4H1834B
B4H0181A