Heating and Air Conditioning: Description and Operation
DescriptionThe PCM will momentarily shut off the compressor under the following conditions.
Engine Temperature
A/C off at 118°C (244°F)
A/C on at 113°C (234°F)
Tip-In Launch Logic (TILL)
A/C off for 0.3 second in automatic transaxle, 1.3 second in manual transaxle if:
Vehicle speed is less than 16 km/h (10 mph), change in Throttle Position (TP) Sensor is greater than 0.8% in 12.5 milliseconds (MS), Manifold Air Temp (MAT) is greater than 45°C (113°F) and Manifold Absolute Pressure (MAP) is greater than 70 kPa (10 psi).
Wide Open Throttle (WOT)
A/C off for 15 seconds if TP sensor is greater than 95% automatic transaxle, 90% manual transaxle back on with TP sensor less than 95% after two seconds.
Compressor Overspeed Protection (COSP)
A/C off if engine rpm is greater than 6500 rpm. A/C on if engine rpm is less than 4500 rpm for two seconds.
Evaporator Low Ambient Protection (ELAP)
If ambient air temperature is between 5° -16°C (40° - 60°F) and vehicle speed is greater than zero the compressor cycles once every 90 seconds depending on inlet air temperature and vehicle speed.
High/Low Pressure Cut-Out Switch
A/C off if discharge pressure is greater than 2758 kPa +71-138 kPa (400 psi +1/-20 psi) and back on at 1724 kPa +7/-345 kPa (250 psi + 11-50 psi). Cooling will run for 180 seconds after A/C is turned off if pressure switch is activated. A/C off if discharge pressure is less than 276 kPa (40 psi).
Cooling Fan Logic
Fan On with A/C switch On. Fan Off at speeds greater than 113 km/h (70 mph) for 180 seconds. Fan runs for 180 seconds after A/C is turned Off.