check engine TOYOTA SEQUOIA 2001 Service Repair Manual

I22614
Condition: Insufficient cooling
Single A/C:
Dual A/C:
I22614
Condition: Insufficient cooling
Single A/C:
Dual A/C:
NOTE: These indications
are shown when the refrig-
eration system has been
opened and the refrigerant
has been charged without
vacuum purging.
± AIR CONDITIONINGAIR CONDITIONING SYSTEM
AC±7
3734 Author: Date:
2005 SEQUOIA (RM1146U)
(6) Refrigerant overcharged or insufficient cooling of
condenser
Symptom seen in
refrigeration systemProbable causeDiagnosisRemedy

Pressure too high on both low
and high pressure sides

No air bubbles seen through the
sight glass even when the engine
rpm is lowered
Unable to develop sufficient per-
formance due to excessive refrig-
erant

Insufficient cooling of condenser
Excessive refrigerant in
cycle"refrigerant overcharged

Condenser cooling
insufficient"condenser fins
clogged or cooling fan faulty
(1) Clean condenser
(2) Check cooling fan with fluid
coupling operation
(3) If (1) and (2) are in normal
state, check amount of refrigerant
and charge proper amount of re-
frigerant
(7) Air present in refrigeration system
Symptom seen in
refrigeration systemProbable causeDiagnosisRemedy

Pressure too high on both low
and high pressure sides

The low pressure piping hot to
the touch

Bubbles seen in sight glass
Air in refrigeration system

Air present in refrigeration sys-
tem

Insufficient vacuum purging
(1) Check compressor oil to see if
it is dirty or insufficient
(2) Evacuate air and charge new
refrigerant

± AIR CONDITIONINGAIR CONDITIONING SYSTEM
AC±9
3736 Author: Date:
2005 SEQUOIA (RM1146U)
3. INSPECT IDLE±UP SPEED
(a) Warm up the engine.
(b) Inspect idle±up speed when the following conditions are
established.

Warm up engine

Blower speed control switch at ºHIº position

A/C switch ON

Temperature control dial at ºCOOLº position
Magnetic clutch conditionIdle±up speed
Magnetic clutch not engaged700 ± 50 rpm
Magnetic clutch engaged780 ± 50 rpm
If idle speed is not as specified, check the Idle control system.
4. INSPECT FOR LEAKAGE OF REFRIGERANT
(a) Perform under the following conditions:

Stop the engine.

Secure good ventilation (If not, the gas leak detec-
tor may react to volatile gases witch are not refriger-
ant, 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 the compressor is OFF: approx. 392 to 588
kPa (4 to 6 kgf/ cm
2, 57 to 85 psi)
(b) Bring the gas leak detector close to the drain hose before
performing the test.
HINT:

After the blower motor stopped, leave the cooling unit for
more than 15 minutes.

Bring the gas leak detector sensor under the drain hose.

When bringing 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 motor linear controller from the cooling unit. Then
insert the gas leak detector sensor into the unit and per-
form 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.

N13790
Low Pressure
Service Valve
High Pressure
Service Valve
I21358
Properly
Charged
Insufficiently
Charged AC±12
± AIR CONDITIONINGAIR CONDITIONING SYSTEM
3739 Author: Date:
2005 SEQUOIA (RM1146U)
3. CHARGE REFRIGERANT INTO REFRIGERANT SYS-
TEM
If there is no leak after refrigerant leak check, charge the proper
amount of refrigerant into the refrigeration system.
CAUTION:

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

Do not open the low pressure side valve when the
system is being charged with liquid refrigerant.
(a) Open the high pressure side valve fully.
(b) Charge specified amount of refrigerant, then close the
high pressure side valve.
HINT:
The system is fully charged if bubbles cannot be seen through
the sight glass.
(c) Partially charge the refrigeration system with refrigerant.
(1) Prepare the vehicle:

Running engine at 1,500 rpm

Single A/C:
Front blower speed control dial at ºHIº posi-
tion

Dual A/C:
Front and rear blower speed set at ºHIº posi-
tion

Single A/C:
Front temperature control dial at ºMAX.
COOLº position

Dual A/C:
Front temperature control dial at ºMAX.
COOLº position
Rear temperature control set at 18.5°C
(65°F)

Air inlet control set at ºRECIRCº

Fully open doors (Sliding roof: closed)
(2) Open the low pressure side valve.
CAUTION:
Do not open the high pressure side valve.
(d) Charge refrigerant until bubbles disappear and check the
pressure on the gauge through the sight glass.

AC3GV±02
I21372
I21373
AC±24
± AIR CONDITIONINGCOOLING UNIT
3751 Author: Date:
2005 SEQUOIA (RM1146U)
COOLING UNIT
ON±VEHICLE INSPECTION
1. INSPECT FOR LEAKAGE OF REFRIGERANT
(a) Remove the console box assembly.
(b) Remove the glove compartment door.
(c) Remove the lower No. 2 finish panel.
(d) Remove the heater to register duct No. 4.
(e) Remove the lower LH finish panel.
(f) Remove the lower cover (See page BO±89).
(g) Remove the blower controller.
(1) Disconnect the connector.
(2) Remove the 2 screws and blower motor linear con-
troller.
(h) Using a gas leak detector, check for leakage.
If there is leakage, check the tightening torque at the joints or
check the evaporator.
(i) Install the blower motor linear controller with the 2 screws.
(j) Install the lower cover.
(k) Install the lower LH finish panel.
(l) Install the lower No.2 finish panel.
(m) Install the glove compartment door (See page BO±97).
2. INSPECT EXPANSION VALVE
(a) Set the manifold gauge set.
(b) Run the engine.
(c) Check quantity of gas with the sight glass in refrigeration
cycle.
(1) Run the engine at 1,500 rpm for at least 5 minutes.
(2) Then check that the high pressure reading is 1.37
to 1.57 Mpa (14 to 16 kgm/cm
2, 199 to 228 psi).
(d) Check the expansion valve.
If the expansion valve is faulty, the low pressure reading will
drop to 0 kPa (0 kgf/cm
2, 0 psi).
HINT:
When the low pressure reading drops to 0 kPa (0 kgf/cm
2, 0
psi), there is no difference in temperature between the IN and
OUT sides of the receiver.
3. INSPECT THERMISTOR RESISTANCE
(a) Disconnect the connector.
(b) Measure the resistance between terminals.
Standard resistance: 1,500 W at 25°C (77°F)
If resistance is not as specified, replace the thermistor.

AC1KZ±05
I21361
3
3
I21362
12
AC±54
± AIR CONDITIONINGCOMPRESSOR AND MAGNETIC CLUTCH
3781 Author: Date:
2005 SEQUOIA (RM1146U)
COMPRESSOR AND MAGNETIC
CLUTCH
ON±VEHICLE INSPECTION
1. SET MANIFOLD GAUGE SET (See page AC±18)
2. START ENGINE
3. INSPECT COMPRESSOR FOR METALLIC SOUND
Check if a metallic sound can be heard from the compressor
when the A/C switch is on.
If a metallic sound cannot be heard, replace the compressor as-
sembly.
4. INSPECT REFRIGERANT PRESSURE
(See page AC±3)
5. STOP ENGINE
6. INSPECT VISUALLY FOR LEAKAGE OF REFRIGER-
ANT FROM SAFETY SEAL
Using a gas leak detector, check for leakage of refrigerant.
If there is any leakage, replace the compressor assembly.
7. REMOVE MANIFOLD GAUGE SET
(See page AC±19)
8. CHECK FOR LEAKAGE OF GREASE FROM CLUTCH
BEARING
9. CHECK FOR SIGNS OF OIL ON PRESSURE PLATE
If necessary, repair or replace.
10. INSPECT MAGNETIC CLUTCH BEARING FOR NOISE
(a) Start the engine.
(b) Check if abnormal noise is heard from near the compres-
sor when the A/C switch is OFF.
If abnormal noise is being emitted, replace the magnetic clutch.
11. INSPECT MAGNETIC CLUTCH OPERATION
(a) Disconnect the connector.
(b) Connect the positive (+) lead from the battery to terminal
3 and the negative (±) lead to body ground.
(c) Check that the magnetic clutch is energized.
If operation is not as specified, replace the magnetic clutch.
12. INSPECT COMPRESSOR LOCK SENSOR RESIS-
TANCE
(a) Disconnect the connector.
(b) Measure the resistance between terminals 1 and 2.
Standard resistance:
165 to 205 W at 20°C (68°F)
If resistance is not as specified, replace the compressor.

AC3I8±02
AC±70
± AIR CONDITIONINGREAR A/C EVAPORATOR
3797 Author: Date:
2005 SEQUOIA (RM1146U)
REAR A/C EVAPORATOR
ON±VEHICLE INSPECTION
1. CHECK QUANTITY OF GAS DURING REFRIGERATION CYCLE
2. SET MANIFOLD GAUGE SET (See page AC±18)
3. RUN ENGINE
(a) Rear blower speed set at ºHIº position
(b) A/C switch ON
(c) Rear temperature control set at 18.5°C (65°F)
(d) Run the engine at 1,500 rpm for at least 5 minutes.
Then check that the high pressure reading is 1.9 to 2.1 MPa (19 to 21 kgf/cm
2, 270 to 300 psi).
4. CHECK EXPANSION VALVE
If the expansion valve is faulty, the low pressure reading will drop to 0 kPa (0 kgf/cm
2, 0 psi).

AC3HK±02
I21801
COOL
WARM AC±78
± AIR CONDITIONINGWATER VALVE
3805 Author: Date:
2005 SEQUOIA (RM1146U)
WATER VALVE
ON±VEHICLE INSPECTION
1. WARM UP ENGINE
2. DISCONNECT WATER VALVE CONTROL CABLE
3. INSPECT WATER VALVE OPERATION
(a) Check that warm air comes out the vent when the water
valve lever is moved to the ºWARMº position.
(b) Check that cool air comes out when the water valve is
moved to the ºCOOLº position.
If operation is not as specified, replace the water valve.
4. CONNECT WATER VALVE CONTROL CABLE

I21455
2
13
4
AC1LS±03
Z13470
Low pressure High pressure
side side
ON (Continuity)
3,140 kpa 196 kpa
(2.0 kgf/cm
2, 28psi)
OFF (No Continuity)(32.0 kgf/cm2, 455psi)
OFF (No Continuity)
I05079
ON (Continuity)
1,520 kpa
1,230 kpa
(12.5 kgf/cm
2, 178psi) OFF (No Continuity)
(15.5 kgf/cm
2, 220psi) Cooling Fan Control AC±92
± AIR CONDITIONINGPRESSURE SWITCH
3819 Author: Date:
2005 SEQUOIA (RM1146U)
PRESSURE SWITCH
ON±VEHICLE INSPECTION
1. SET MANIFOLD GAUGE SET (See page AC±18)
2. DISCONNECT CONNECTOR
3. RUN ENGINE AT APPROX. 2,000 rpm
4. SET BLOWER SPEED CONTROL SWITCH TO ºHIº
POSITION
5. SET TEMPERATURE CONTROL LEVER TO ºMAX.
COOLº POSITION
6. A/C SWITCH ON
7. INSPECT PRESSURE SWITCH OPERATION
(a) Connect the positive (+) lead from the ohmmeter to termi-
nal 4 and the negative (±) lead to terminal 1.
(b) Check continuity between terminals when refrigerant
pressure is changed, as shown in the illustration.
If operation is not as specified, replace the pressure switch.
8. Cooling fan control:
INSPECT PRESSURE SWITCH OPERATION
9. STOP ENGINE AND REMOVE MANIFOLD GAUGE
SET
10. CONNECT CONNECTOR TO PRESSURE SWITCH
(a) Connect the positive (+) lead from the ohmmeter to termi-
nal 2 and the negative (±) lead to terminal 3.
(b) Check continuity between terminals when refrigerant
pressure is changed, as shown in the illustration.
If operation is not as specified, replace the pressure switch.
11. STOP ENGINE AND REMOVE MANIFOLD GAUGE
SET
12. CONNECT CONNECTOR TO PRESSURE SWITCH

AC1LZ±05
I21428
1 2
AC±96
± AIR CONDITIONINGCONDENSER FAN
3823 Author: Date:
2005 SEQUOIA (RM1146U)
CONDENSER FAN
ON±VEHICLE INSPECTION
1. INSPECT CONDENSER FAN OPERATION
Inspect the fan operation under the following conditions, as
shown in the chart.
Test conditions:

Start engine

Blower speed control switch position ºHIº

Temperature control dial at ºCOOLº position

Set manifold gauge set

A/C switch ON
ConditionFan operation (Fan speed)
Refrigerant pressure is less than
1,520 kPa (15.5 kgf/cm2, 220 psi)OFF
Refrigerant pressure is 1,520 kPa
(15.5 kgf/cm2, 220 psi) or aboveRotate
If operation is not as specified, proceed to the next inspection.
2. INSPECT CONDENSER FAN MOTOR OPERATION
(a) Disconnect the fan connector.
(b) Connect the battery and ammeter.
(c) Check that the fan rotates smoothly, and then check the
reading on the ammeter.
Specified amperage: 9.2 to 11.0 A at 20°C (68°F)
If operation is not as specified, replace the fan motor.
If operation is as specified, check the pressure switch, cooling
fan relays and water temp. switch.

05_SEQUOIA_U (L/O 0408)
ix
2005 SEQUOIA from Aug. '04 Prod. (OM34424U)
On±pavement and off±road
driving tips
This vehicle belongs to the utility vehicle class. Utility
vehicles have a significantly higher rollover rate than
other types of vehicles. This vehicle will handle and
maneuver differently from an ordinary passenger car be-
cause it is designed for off±road use also. In addition,
this vehicle has a higher ground clearance and center of
gravity than that of an ordinary passenger car. This
vehicle design feature causes this type of vehicle to be
more likely to rollover. Failure to operate this vehicle
correctly may result in loss of control, accidents or
vehicle rollover causing death or serious injury. Be sure
to read ªOff±road vehicle precautionsº on page 334 in
Section 2 and ªOff±road driving precautionsº on page
365 in Section 3.
Leak detection pump
This pump performs fuel evaporation leakage check. This
check is done approximately five hours after the engine is
turned off. So you may hear sound coming from under-
neath the luggage compartment for several minutes. It
does not indicate a malfunction.