A/C CUT-OFF CONTROL [SKYACTIV-G 2.0, SKYACTIV-G 2.5]

id0140g2206200


Outline

•  To improve drive performance and A/C compressor reliability, the A/C relay is turned off at the appropriate timing according to the engine operation conditions, and the A/C operation is controlled.

Block Diagram

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Operation

•  The PCM stops current to the A/C relay when any of the following conditions are met:

A/C cut-off control operation conditions

Operation condition

While A/C relay not energized

Purpose
At engine start
Approx. 4 s
Improved startability
When engine is restarted by i-stop control
Approx. 3 s
Improved startability
When high engine speed (approx. 6,700 rpm or more)
Approx. 5 s elapsed since engine speed was 6,200 rpm or less
A/C compressor reliability assurance
Accelerated
Approx. 5 s
Acceleration from standstill/acceleration performance improvement
Time under i-stop control, vehicle speed of 1km/h {0.6 mph} or less
—
i-stop function reliability improvement
Refrigerant pressure 3.14 MPa {32.0 kgf/cm2, 455 psi} or more
Refrigerant pressure decreases to 2.55 MPa {26.0 kgf/cm2, 370 psi} or less
A/C compressor reliability assurance
Refrigerant pressure of 0.196 MPa {2.00 kgf/cm2, 28.4 psi} or less continues for 5 s or more
Refrigerant pressure of 0.226 MPa {2.30 kgf/cm2, 32.8 psi} or more continues to 5 s or more
A/C compressor reliability assurance
Drive-by-wire control malfunction
—
Reverse driving performance assurance
Panic braking determined
—
Load performance assurance
ECT sensor malfunction
—
Engine protection
When high engine coolant temperature (approx. 113 °C {235 °F} or more)
High engine coolant temperature: Continuously cuts off the A/C, and if the engine coolant temperature decreases, it continues to cut-off the A/C.
Engine protection
Travel on ascending road
—
Ascent performance improvement