HOLDEN GEN III V8, Обучение по обслуживанию

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GEN III V8 ENGINE MANAGEMENT
A/C REQUEST SIGNAL AND A/C CLUTCH CONTROL WITH ECC
The Electronic Climate Control (ECC) module requests the PCM to turn the A/C compressor clutch on or off via
the PIM and the serial data bus normal mode message. The ECC module monitors information from it's sensors
and switches and determines if the A/C compressor clutch should be on or off. The ECC control module will
then request the PCM to turn the A/C compressor clutch on or off when required.
The PCM on receiving a request to turn on the A/C compressor will:
1 . Adjust the Idle Air Control (IAC) valve position to compensate for the additional load placed on the engine
by the air conditioning compressor, and then...
2. Energise the A/C compressor relay, to operate the A/C compressor if the pressure in the A/C system is
within the correct operating range.
The PCM on receiving a request to turn on the A/C compressor, monitors the A/C pressure, coolant
temperature and RPM to determine A/C clutch operation.
GEN III V8 ENGINE MANAGEMENT Page • 69