TOYOTA SIENNA 2007 Service Repair Manual

AIR CONDITIONING – AIR CONDITIONING SYSTEM (for Automatic Air Conditioning Sys-
tem)AC–17
AC
E109264E10

AC–168AIR CONDITIONING – REFRIGERANT
AC
REFRIGERANT
ON-VEHICLE INSPECTION
1. INSPECT REFRIGERANT PRESSURE WITH
MANIFOLD GAUGE SET
(a) This method uses a manifold gauge set to locate
problem areas. Read the manifold gauge pressure
when these conditions are established.
Test conditions:
• Temperature at the air inlet is 30 to 35
C (86 to
95
F).
• Engine is running at 1,500 rpm.
• All doors are fully open.
• Blower speed control switch is at HI.
• Temperature control switch is at MAX. COOL.
• A/C switch is ON.
(b) Gauge readings (Reference)
I030081E19

AIR CONDITIONING – REFRIGERANTAC–169
AC
(1) Normally functioning refrigeration system
Gauge reading
(2) The A/C system periodically changes between
normal and improper function due to moisture
in the refrigerant system.
(3) The A/C system does not function effectively
due to insufficient cooling.
E050573E05
Pressure side Refrigerant volume
Low
0.15 to 0.25 MPa (1.5 to 2.5 kgf/cm
2)
High
1.37 to 1.57 MPa (14 to 16 kgf/cm
2)
Symptoms Probable Cause Diagnosis Corrective Actions
During operation, pressure on low
- pressure side cycles between
normal and vacuumMoisture in refrigeration system
freezes at expansion valve orifice,
causing temporary stop of cycle.
However, when melted, normal
state is restored- Drier is overly saturated
- Moisture in refrigeration system
freezes at expansion valve orifice
and blocks refrigerant circulation1. Replace cooler drier
2. Remove moisture from cycle
by repeatedly evacuating air
3. Supply appropriate volume of
new refrigerant
I022117E17
Symptoms Probable Cause Diagnosis Corrective Actions
- Pressure low on both low and
high-pressure sides
- Cooling performance insufficientGas leakage from refrigeration
system- Insufficient refrigerant
- Refrigerant leakage1. Check for gas leakage and
repair if necessary
2. Supply appropriate volume of
new refrigerant
3. If indicated pressure value
close to 0 when connected to
gauge, create vacuum after
inspecting and repairing the
location of leakage
I022118E10

AC–170AIR CONDITIONING – REFRIGERANT
AC
(4) The A/C system does not function effectively
due to poor circulation of the refrigerant.
(5) The A/C system does not function intermittently
because the refrigerant does not circulate.
(6) The A/C system does not function effectively
due to overcharged refrigerant or insufficient
cooling of the condenser.
Symptoms Probable Cause Diagnosis Corrective Actions
- Pressure low on both low and
high-pressure sides
- Frost exists on piping from
condenser to A/C unitRefrigerant flow obstructed by dirt
in condenserCondenser clogged Replace condenser
I022119E11
Symptoms Probable Cause Diagnosis Corrective Actions
- Vacuum indicated on low-
pressure side, and extremely low
pressure indicated on high-
pressure side
- Frost or condensation seen on
piping on both sides of condenser
or expansion valve- Refrigerant flow obstructed by
moisture or dirt in refrigeration
system
- Refrigerant flow obstructed by
gas leakage from expansion
valveRefrigerant does not circulate1. Check expansion valve
2. Clean expansion valve by
blowing air
3. Replace condenser
4. Evacuate air and charge
appropriate volume of new
refrigerant
5. For gas leakage from
expansion valve, replace
expansion valve
I022120E10
I022121E11

AIR CONDITIONING – REFRIGERANTAC–171
AC
(7) The A/C system does not function due to air in
the refrigeration system.
CAUTION:
The low-pressure piping may be very hot
and cause serious burns.
(8) The A/C system does not function effectively
due to an expansion valve malfunction.
Symptoms Probable Cause Diagnosis Corrective Actions
Pressure extremely high on both
low and high-pressure sides- Excessive refrigerant
- Cooling performance of
condenser insufficient- Condenser is dirty
- Condenser fan motor is
malfunctioning
- Excessive refrigerant1. Clean condenser
2. Check condenser fan motor
operation
3. If 1 and 2 normal, check the
amount of refrigerant and supply
appropriate volume of refrigerant
Symptoms Probable Cause Diagnosis Corrective Actions
- Pressure extremely high on both
low and high-pressure sides
- The low-pressure piping is too
hot to touchAir in refrigeration system- Air in refrigeration system
- Vacuum purging insufficient1. Check if compressor oil is dirty
or insufficient
2. Evacuate air and charge new
refrigerant
I022122E12
Symptoms Probable Cause Diagnosis Corrective Actions
-Pressure extremely high on both
low and high-pressure sides
-Frost or condensation on piping
on low-pressure sideProblem with expansion valve- Excessive refrigerant in low
pressure piping
- Expansion valve too wide openReplace expansion valve
I022123E12

AC–172AIR CONDITIONING – REFRIGERANT
AC
(9) The A/C system does not function due to a
defective compressor.
Gauge readings (Reference)
Symptoms Probable Cause Diagnosis Corrective Actions
-Pressure extremely high on both
low and high-pressure sides
-Pressure extremely low on high-
pressure sideInternal leakage in compressor- Compression failure
- Leakage from damaged valve or
broken sliding partsRepair or replace compressor
I022124E11
I030081E21

AIR CONDITIONING – REFRIGERANTAC–173
AC
REPLACEMENT
1. DISCHARGE REFRIGERANT FROM
REFRIGERATION SYSTEM
SST 07110-58060 (07117-58080, 07117-58090,
07117-78050, 07117-88060, 07117-88070,
07117-88080)
(a) Turn the A/C switch to ON.
(b) Operating the cooler compressor at the engine rpm
of approx. 1,000 for 5 to 6 minutes, circulate the
refrigerant and collect the compressor oil remaining
in each component into the cooler compressor as
much as possible.
(c) Stop the engine.
(d) Let the refrigerant gas out.
SST 07110-58060 (07117-58080, 07117-78050,
07117-88060, 07117-88070, 07117-88080)
2. CHARGE REFRIGERANT
(a) Using a vacuum pump, perform a vacuum purging.
(b) Charge refrigerant, HFC-134a (R134a).
Standard:
780 +- 30 g (27.5 +- 1.06 oz.)
SST 07110-58060 (07117-58060, 07117-58070,
07117-58080, 07117-58090, 07117-78050,
07117-88060, 07117-88070, 07117-88080)
3. WARM UP ENGINE
4. INSPECT REFRIGERANT LEAK
(a) Using a gas leak detector, check for leakage of the
refrigerant.
I030082E10

AC–18AIR CONDITIONING – AIR CONDITIONING SYSTEM (for Automatic Air Conditioning Sys-
tem)
AC
DATA LIST / ACTIVE TEST
1. DATA LIST
HINT:
Using the intelligent tester to read the Data List allows
the values or states of switches, sensors, actuators and
other items to be read without removing any parts. This
non-intrusive inspection can be very useful because
intermittent conditions or signals may be discovered
before parts or wiring is disturbed. Reading the Data List
information early in troubleshooting is one way to save
diagnostic time.
(a) Connect the intelligent tester to the DLC3.
(b) Turn the ignition switch to the ON position.
(c) From the display on the tester, read the "DATA
LIST".
AIR CONDITIONER / DATA LIST
Tester Display Measurement Item/Range Normal Condition Diagnostic Note
ROOM TEMPRoom temperature sensor / min.:
-6.5
C (20.3F), max.: 57.25C
(135.05
F)Actual cabin temperature -
AMBI TEMP SENSAmbient temperature sensor /
min.: -23.3
C (-9.94F), max.:
65..95C (150.71F)Actual ambient temperature -
AMBI TEMPAdjusted ambient temperature /
min.: -30.8
C (-23.44F), max.:
50.8
C (123.44F)--
EVAP TEMPEvaporator temperature sensor /
min.: -29.7
C (-21.46F), max.:
59.55
C (139.19F)Actual evaporator temperature -
SOLAR SENS-DSolar sensor (D side) / min.: 0,
max.: 255Changes depending on
brightness (D side)-
SOLAR SENS-PSolar sensor (P side) / min.: 0,
max.: 255Changes depending on
brightness (P side)-
COOLANT TEMPEngine coolant temperature /
min.: 1.3
C (34.34F), max.:
90.55C (194.99F)Actual engine coolant
temperature-
SET TEMP-DSet temperature (D side) / min.: 0,
max. 255Actual set temperature (D side) -
SET TEMP-PSet temperature (P side) / min.: 0,
max. 255Actual set temperature (P side) -
ESTIMATE TEMP-DEstimated temperature (D side) /
min.: -358.4
C (-613.12F), max.:
358.4
C (677.12F)--
ESTIMATE TEMP-PEstimated temperature (P side) /
min.: -358.4
C (-613.12F), max.:
358.4
C (677.12F)--
A/M DAMP POS-DAir mix damper position (D side) /
min.: -14%, max.: 113.5%Changes depending on the set
temperature (D side)-
A/M DAMP POS-PAir mix damper position (P side) /
min.: -14%, max.: 113.5%Changes depending on the set
temperature (P side)-
A/I DAMP POSAir inlet damper position / min.: -
14%, max.: 113.5%Changes depending on air inlet
damper position-
A/O DAMP POSAir outlet damper position / min.: -
14%, max.: 113.5%Changes depending on air outlet
damper position-
A/M DAMP TARG-DAir mix damper target position (D
side) / min.: -14%, max.: 113.5%Changes depending on the set
temperature (D side)-
A/M DAMP TARG-PAir mix damper target position (P
side) / min.: -14%, max.: 113.5%Changes depending on the set
temperature (P side)-

AIR CONDITIONING – AIR CONDITIONING SYSTEM (for Automatic Air Conditioning Sys-
tem)AC–19
AC
HINT:
*1: It differs depending on the user setting.
2. ACTIVE TEST
HINT:
Using the intelligent tester to perform Active Tests allows
relays, VSVs, actuators and other items to be operated
without removing any parts. This non-intrusive functional
inspection can be very useful because intermittent
operation may be discovered before parts or wiring is
disturbed. Performing Active Tests early in
troubleshooting is one way to save diagnostic time. Data
List information can be displayed while performing Active
Tests.
(a) Connect the intelligent tester to the DLC3.
A/I DAMP TARGAir inlet damper target position /
min.: -14%, max.: 113.5%Changes depending on air inlet
damper position-
A/O DAMP TARGAir outlet damper target position /
min.: -14%, max.: 113.5%Changes depending on air outlet
damper position-
BLOWER LEVELBlower motor speed level / min.:
Level 0, max.: Level 31Changes depending on blower
level-
REAR ROOM TEMPRoom temperature sensor (Rear)
/ min.: -6.5
C (20.3F), max.:
57.25C (135.05F)Actual cabin temperature (Rear) -
R-EVAP TEMP SENRr. EVAP temperature sensor
(Rear) / min.: -29.7
C (-21.46F),
max.: 59.55
C (139.19F)Actual evaporator temperature
(Rear)-
SET TEMP REARSet temperature (Rear) / min.: 0,
max. 255Actual set temperature -
ESTIMATE TEMP-REstimated temperature (Rear) /
min.: -358.4
C (-613.12F), max.:
358.4
C (677.12F)--
A/M DAMP POS-RAir mix damper position (Rear) /
min.: -14%, max.: 113.5%Changes depending on the set
temperature (Rear)-
A/O DAMP POS-RAir outlet mode damper position
(Rear) / min.: -14%, max.: 113.5%Changes depending on air outlet
damper position (Rear)-
A/M DAMP TARG-RAir mix damper target position
(Rear) / min.: -14%, max.: 113.5%Changes depending on the set
temperature (Rear)-
A/O DAMP TARG-RAir outlet damper target position
(Rear) / min.: -14%, max.: 113.5%Changes depending on air outlet
damper position (Rear)-
BLOWER LEVEL-RBlower motor speed level (Rear) /
min.: Level 0, max: Level 31Changes depending on blower
level (Rear)-
SET TEMP SHIFT Shift set temperatureChanges depending on shift set
temperature *1-
AIR INLET MODE Air inlet modeChanges depending on air inlet
mode *1-
COMPRESSOR MODE Compressor modeChanges depending on
compressor mode *1-
COMPRS/DEF MODE Compressor/DEF operation modeChanges depending on
compressor/DEF operation mode
*1-
FOOT/DEF OPER Foot/DEF auto modeChanges depending on Foot/DEF
auto mode *1-
AUTO BLOW UPFoot/DEF automatic blow up
functionChanges depending on Foot/DEF
automatic blow up function *1-
#CODESNumber of Trouble Codes / min.:
0, max.: 255-- Tester Display Measurement Item/Range Normal Condition Diagnostic Note

AC–20AIR CONDITIONING – AIR CONDITIONING SYSTEM (for Automatic Air Conditioning Sys-
tem)
AC
(b) Turn the ignition switch to the ON position.
(c) From the display on the tester, read the "ACTIVE
TEST".
Tester Display Test Part Control Range Diagnostic Note
BLOWER MOTOR Blower motor min.: Level 0, max.: Level 31 -
AIR MIX DAMP-D Air mix damper (D side) min.: -14%, max: 113.5% -
AIR MIX DAMP-P Air mix damper (P side) min.: -14%, max: 113.5% -
A/O MODE DAMP-DAir outlet damper position (D
side)min.: -14%, max: 113.5% -
A/I DAMP-LINEAR Air inlet damper position (linear) min.: -14%, max: 113.5% -
REAR BLOWER Blower motor (Rear) OFF, LO, HI -
A/O MODE DAMP-R Air outlet damper position (Rear) min.: -14%, max: 113.5% -
AIR MIX DAMP-R Air mix damper (Rear) min.: -14%, max: 113.5% -
A/C MAG CLUTCH Magnetic clutch relay OFF, ON -