Bentley Volkswagen.Golf.Jetta.R32.Official.Factory.Repair.Manual.1999-2005

Pressures, checking on vehicles
Página 25 de 33
- Low pressure settles as a
function of control current for A/C
Compressor Regulator Valve
N280 within compressor output
range in tolerance range.
- Under unfavorable conditions
(very high ambient temperatures,
high humidity), compressor output
may not always be sufficient to
attain the specified value.
- The specified operating current
for the regulating valve must be
greater than 0.3 A in order to
ensure reliable valve actuation.
- 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)
Repair Manual, Heating & Air
Conditioning, Repair Group 87 ,
.
- 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).
Possible deviation from
specification
- High pressure remains constant
or only increases slightly (above
pressure with engine stopped).
- Low pressure quickly drops to
value in graph or below.
- Required cooling output is not
attained.
- High pressure normal.
Possible cause
- Activation of A/C Compressor
Regulator Valve N280
malfunctioning
- Not enough refrigerant in
refrigerant circuit.
Corrective action
- Check activation of
Compressor Regulator Valve
N280 .
- Localize leak using leak detec
and eliminate.
- Re-charge refrigerant circuit.
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13/2/2005