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Engine, Engine Attaching Parts Functional Overview Eng. Cooling Module Opel Astra G

Survey of Engine Cooling Module Operation

The following table shows the actuation of the radiator fans according to the coolant temperature.

TriggeredConditionActuation of
Temperature stage 0< 98 °CNo fan
Temperature stage 0< 98 °CSupply and expulsion fans in series
+ compressorAir conditioning "ON"
Temperature stage 1≥ 98 °C = "ON"Supply and expulsion fans in series
≤ 95 °C = "OFF"
Temperature stage 2≥ 103 °C = "ON"Supply and expulsion fans parallel via series resistor
≤ 98 °C = "OFF"
Temperature stage 3≥ 106 °C = "ON"Supply and expulsion fans parallel to battery voltage
≤ 103 °C = "OFF"
Fan run-on≥ 105 °C = "ON"First fan speed -
Run-on period: 2 min.Supply and expulsion fans in series

2.15.2 Survey of Engine Cooling Module Operation

The following table shows how the compressor and radiator fans are actuated depending on the coolant high pressure:

TriggeredConditionActuation of
Low pressure range< 180 kPaCompressor "OFF"
Low pressure range> 215 kPaCompressor "ON"
High pressure range> 1200 kPa = "ON"Supply and expulsion fans in series
< 900 kPa = "OFF"
High pressure range> 1700 kPa = "ON"Supply and expulsion fans parallel, each via series resistor
< 1400 kPa = "OFF"
High pressure range> 2100 kPa = "ON"Supply fan to battery voltage
< 1800 kPa = "OFF"Expulsion fan via series resistor
High pressure range> 2400 kPa = "ON"Supply and expulsion fans parallel to battery voltage
< 2100 kPa = "OFF"
High pressure range> 3000 kPa = "ON"Compressor "OFF"
< 2300 kPa = "OFF"Compressor "ON"
Fan run-on> 105 °C = "ON"First fan speed -
Run-on period: 2 min.Supply and expulsion fans in series