Toyota Prius 2010 Repair Manual page 334

Symptom
During operation,
pressure on low
pressure side
cycles between
normal and
vacuum
(3) Insufficient cooling
Symptom
Pressure is low on
both low and high
pressure sides
Bubbles are seen
through sight glass
continuously
Insufficient cooling
performance
(4) Poor circulation of refrigerant
Symptom
2010 Toyota Prius
Probable Cause
Moisture in the AC
system will freeze at the
expansion valve orifice,
causing the refrigeration
cycle to temporarily stop
After the system stops,
and warms up again, the
ice will melt and normal
operation will be
temporarily restored
Probable Cause
Gas leaks from
the refrigeration
system
Diagnosis
Cooler dryer
(integrated into
condenser tank) in
oversaturated state
Moisture in
refrigeration system
freezes at expansion
valve orifice and blocks
circulation of
refrigerant
Diagnosis
Insufficient
refrigerant
Refrigerant
leaking
Probable Cause
Corrective Action
1. Replace cooler
dryer
2. Remove moisture
in system by
repeatedly
evacuating air
3. Supply a proper
amount of new
refrigerant
Corrective Action
1. Check for gas leaks and
repair if necessary
2. Supply a proper amount of
new refrigerant
3. If the gauge indicates a
pressure of close to 0, then it
will be necessary to evacuate
the system after repairing the
leak
Corrective
Diagnosis
Repair Manual
Action