S60 L5-2.4L Turbo VIN 54 B5244T5 (2005)
engine control module (ECM) determines when the compressor must operate. If any of the following conditions are met the compressor is disconnected:
-
high engine coolant temperature (ECT)
-
wide open throttle (WOT)
-
the engine has just been started
-
overpressure in the air conditioning (A/C) system.
When the engine is started the engine control module (ECM) activates the air conditioning compressor for a short period even if the climate control
module (CCM) has not transmitted a request for this. This is carried out for diagnosis. This check is carried out at all temperatures exceeding -6 degrees
C.
The advantage in allowing the engine control module (ECM) to control the air conditioning compressor is that it can delay compressor activation
somewhat, if the idling speed must be compensated for the extra load for example.
Cooling system (B8444S only)
The engine control module (ECM) controls the variable A/C compressor. When the A/C switch on the dashboard environment panel is activated, a
request is transmitted via the control area network (CAN) to the engine control module (ECM) about the activation of the compressor. The engine
control module (ECM) calculates the current to open the valve to control the variable A/C compressor. If any of the following conditions are met, the
valve that activates the compressor is not opened:
-
high engine coolant temperature (ECT)
-
wide open throttle (WOT)
-
the engine has just been started
-
overpressure in the air conditioning (A/C) system.
When the engine is started the engine control module (ECM) activates the air conditioning compressor for a short period even if the climate control
module (CCM) has not transmitted a request for this.
This is carried out for diagnosis and maintenance at all temperatures exceeding 0 degrees C.
For more information on the A/C compressor, see Design and function, engine control module (ECM)
Sun sensor (electronic climate control only)
Twilight sensor
