2001 TOYOTA PRIUS Service Repair Manual

I01450
Condition: Insufficient cooling
I01393
Condition : Does not cool AC±8
± AIR CONDITIONINGAIR CONDITIONING SYSTEM
2001 PRIUS (RM778U)
(8) Expansion valve improperly
Symptom seen in
refrigeration systemProbable causeDiagnosisRemedy
 Pressure too high on both low
and high pressure sides
 Frost or large amount of dew on
piping on low pressure side
Trouble in expansion valve
 Excessive refrigerant in low
pressure piping
 Expansion valve opened too
wide
Check expansion valve
Replace if defective
(9) Defective compression compressor
Symptom seen in
refrigeration systemProbable causeDiagnosisRemedy
 Pressure too high on low and
high pressure sides
 Pressure too low on high pres-
sure side
Internal leak in compressor
 Compression defective
 Valve leaking or broken sliding
parts
Repair or replace compressor

N14519
Drain Hose
± AIR CONDITIONINGAIR CONDITIONING SYSTEM
AC±9
2001 PRIUS (RM778U)
3. INSPECT FOR LEAKAGE OF REFRIGERANT
(a) Perform in these conditions:
Stop engine.
Secure good ventilation (If the gas leak detector
may not react to volatile gases which are not refrig-
erant, such as evaporated gasoline and exhaust
gas.)
Repeat the test 2 or 3 times.
Make sure that there is some refrigerant remaining
in the refrigeration system.
When compressor is OFF: approx. 392 ± 588 kPa
(4 ± 6 kgf/ cm
2, 57 ± 85 psi)
(b) Bring the gas leak detector close to the drain hose before
performing the test.
HINT:
After the blower motor has stopped, leave the cooling unit
for more than 15 minutes.
Expose the gas leak detector sensor under the drain
hose.
When bring the gas leak detector close to the drain hose,
make sure that the gas leak detector does not react to the
volatile gases.
If such reaction is unavoidable, the vehicle must be lifted up.
(c) If gas leak is not detected on the drain hose, remove the
blower resistor from the cooling unit. Then insert the gas
leak detector sensor into the unit and perform the test.
(d) Disconnect the connector and leave the pressure switch
for approx. 20 minutes. Then bring the gas leak detector
close to the pressure switch and perform the test.
(e) Bring the gas leak detector close to the refrigerant lines
and perform the test.

AC±10
± AIR CONDITIONINGAIR CONDITIONING SYSTEM
2001 PRIUS (RM778U)
4. INSPECT IDLE±UP SPEED
(a) Activate inspection mode (See page IN±10).
(b) Inspect idle±up speed when the these conditions are es-
tablished.
Test conditions:
Idle speed set correctly.
Steering wheel straight ahead
Blower speed control dial at HI
A/C switch ON
Magnetic clutch conditionIdle speed
Magnetic clutch not engaged1,000 ±50 rpm
Magnetic clutch engaged1,000 ±50 rpm
If idle speed is not as specified, check the engine ECU and
throttle body.

AC20C±03
N13793
Charging Cylinder High Pressure
Service Valve Low Pressure
Service ValvePush
Air
N13792
Gas Leak
Detector AC±12
± AIR CONDITIONINGAIR CONDITIONING SYSTEM
2001 PRIUS (RM778U)
CHARGING
1. INSTALL CHARGING CYLINDER
HINT:
When handling the charging cylinder, always follow the direc-
tions given in the instruction manual.
(a) Charge the proper amount of refrigerant into the charging
cylinder.
(b) Connect the center hose to the charging cylinder.
CAUTION:
Do not open both high and low hand valves of manifold
gauge set.
(c) Open the valve of charging cylinder.
(d) Press the valve core on the side of manifold gauge and
expel the air inside of the center hose.
2. INSPECT REFRIGERATION SYSTEM FOR LEAKS
(a) Open the high pressure hand valve and charge refriger-
ant.
(b) When the low pressure gauge indicates 98 kPa
(1 kgf/cm
2, 14 psi) close the high pressure hand valve.
(c) Using a gas leak detector, check the system for leakage.
If leak is found, repair the faulty component or connection.
CAUTION:
Use the refrigerant recovery/ recycling machine to recover
the refrigerant whenever replacing parts.

N13790
Low Pressure
Service Valve
High Pressure
Service Valve
I17972
Properly
Charged
Insufficiently
Charged
± AIR CONDITIONINGAIR CONDITIONING SYSTEM
AC±13
2001 PRIUS (RM778U)
3. CHARGE REFRIGERANT INTO REFRIGERANT SYS-
TEM
If there is no leak after refrigerant leak check, charge the proper
amount of refrigerant into refrigeration system.
CAUTION:

Never run the engine when charging the system
through the high pressure side.

Do not open the low pressure hand a valve when the
system is being charged with liquid refrigerant.
(a) Open the high pressure hand valve fully.
(b) Charge specified amount of refrigerant, then close the
high pressure hand valve.
HINT:
A fully charged system is indicated by the sight glass being free
of any bubbles.
(c) Charge partially refrigeration system with refrigerant.
(1) Set vehicle in these conditions:

MAX. switch ON

Blower speed control set at ºHIº

Temperature control set at ºMAX. COOLº

Air inlet control set at ºRECIRCº

Running engine at 1,500 rpm

Fully open doors
(2) Open the low pressure hand valve.
CAUTION:
Do not open the high pressure hand valve.
(d) Charge refrigerant until bubbles disappear and check the
pressure on the gauge through the sight glass.
(e) Replenishment to be 100 ± 50 g after bubbles disapper.