New Beetle L4-2.0L (AVH) (2005)
Expansion Valve: Testing and Inspection
Expansion Valve, Receiver and A/C Compressor Regulator Valve N280 (Externally Regulated
Compressor), Checking
Expansion Valve, Receiver and A/C Compressor Regulator Valve N280 (Externally Regulated Compressor), Checking
NOTE:
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Connect service station. See: Testing and Inspection/Component Tests and General Diagnostics/Working With Service Station
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Observe test conditions. See: Testing and Inspection/Component Tests and General Diagnostics/Pressures In Refrigerant Circuit, Checking (Using
Service Station)
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Set engine speed to 2000 RPM.
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Observe pressure gauge of service station.
NOTE:
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Switching pressures for actuation of A/C Compressor Regulator Valve N280 and Coolant Fan V7 are vehicle-specific.
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Pressures must be measured at service connections; component locations of these connections are vehicle-specific.
Specified values:
High pressure side:
Increasing from initial pressure (on connecting pressure gauges) to 20 bar.
Low pressure side:
Decreasing from initial pressure (on connecting pressure gauges) to value in graph.
A - Low pressure (measured at service connection) in bar absolute
B - Control current for A/C Compressor Regulator Valve N280
C - Permissible tolerance range.
NOTE:
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Under unfavorable conditions (very high ambient temperatures, high humidity), pressure on high-pressure side may increase to max. 29 bar.
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Control current - B - is displayed in measured value block.
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High pressure measured by High Pressure Sensor G65 is displayed in measured value block.
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Low pressure settles as a function of control current for A/C Compressor Regulator Valve N280 within compressor output range in tolerance
range.
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Under unfavorable conditions (very high ambient temperatures, high humidity), compressor output may not always be sufficient to attain the
specified value.
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The specified operating current for the regulating valve must be greater than 0.3 A in order to ensure reliable valve actuation.
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In the setting "maximum cooling output" control current is regulated to approx. 0.65 A up to 0.85 A (vehicle specific, displayed in measured value
block).
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At absolute pressure, 0 bar corresponds to absolute vacuum. Normal ambient pressure equals 1 bar absolute pressure. 0 pressure corresponds to
an absolute pressure of one bar on most pressure gauges (indicated by -1 bar below 0).