O2 sensor TOYOTA SEQUOIA 2001 Service Repair Manual

EC0O0±01
B17520
B17521
B17522
B17523
B17524
EC±22
± EMISSION CONTROLSECONDARY AIR INJECTION SYSTEM
2730 Author: Date:
2005 SEQUOIA (RM1146U)
REMOVAL
1. REMOVE THROTTLE BODY COVER
2. REMOVE INTAKE MANIFOLD (See page EM±36)
3. REMOVE VSV FOR AIR INJECTION SYSTEM
(a) Remove the 2 bolts and 2 VSVs from the intake manifold.
(b) Remove the 2 vacuum hoses from the 2 VSVs.
4. REMOVE AIR PUMP ASSEMBLY
(a) Disconnect the air hose No.2 from the air switching valve.
(b) Disconnect the air switching valve connector.
(c) Disconnect the pressure sensor connector for the air in-
jection system.
(d) Remove the 4 bolts and air pump assembly.
5. REMOVE NO. 2 AIR SWITCHING VALVE
(a) Remove the 4 nuts and 2 gaskets, and disconnect the 2
No.3 air tubes from the exhaust manifolds.
(b) Remove the 4 bolts, 2 gaskets and the 2 No.3 air tubes
from the 2 No.2 air switching valves.
(c) Remove the 4 bolts, 2 gaskets and the 2 No.2 air switch-
ing valves from the rear water by±pass joint.
(d) Remove the 2 vacuum hoses from the No.2 air switching
valves.
6. REMOVE AIR INJECTION CONTROL DRIVER
(a) Disconnect the 2 connectors from the air injection control
driver.
(b) Remove the 2 bolts and air injection control driver from
the body.

EC0O1±01
B17525
B17526
± EMISSION CONTROLSECONDARY AIR INJECTION SYSTEM
EC±23
2731 Author: Date:
2005 SEQUOIA (RM1146U)
DISASSEMBLY
1. REMOVE PRESSURE SENSOR
(a) Remove the vacuum hose from the pressure sensor and
air switching valve.
(b) Remove the 2 bolts and pressure sensor from the air
switching valve.
2. REMOVE AIR SWITCHING VALVE
(a) Remove the 2 bolts and air switching valve from the air
pump bracket.
(b) Remove the No.1 air hose from the air switching valve
and air pump.

EC0O3±01
B17526
B17525
± EMISSION CONTROLSECONDARY AIR INJECTION SYSTEM
EC±25
2733 Author: Date:
2005 SEQUOIA (RM1146U)
REASSEMBLY
1. INSTALL AIR SWITCHING VALVE
(a) Install the No.1 air hose to the air switching valve and air
pump.
(b) Install the air switching valve with the 2 bolts to the air
pump bracket.
Torque: 16 N´m (163 kgf´cm, 12 ft´lbf)
2. INSTALL PRESSURE SENSOR
(a) Install the pressure sensor with the 2 bolts to the air
switching valve.
Torque: 5.0 N´m (55 kgf´cm, 48 in.´lbf)
(b) Install the vacuum hose to the pressure sensor and air
switching valve.

EC0O4±01
B17524
B17523
B17522
B17521
B17520
EC±26
± EMISSION CONTROLSECONDARY AIR INJECTION SYSTEM
2734 Author: Date:
2005 SEQUOIA (RM1146U)
INSTALLATION
1. INSTALL AIR INJECTION CONTROL DRIVER
(a) Install the air injection control driver with the 2 bolts to the
body.
Torque: 18 N´m (184 kgf´cm, 13 ft´lbf)
(b) Connect the 2 connectors to the air injection control driv-
er.
2. INSTALL NO. 2 AIR SWITCHING VALVE
(a) Connect the 2 vacuum hoses to the No.2 air switching
valves.
(b) Install 2 new gaskets and 2 No.2 air switching valves with
the 4 bolts to the rear water by±pass joint.
Torque: 10 N´m (102 kgf´cm, 7 ft´lbf)
(c) Install 2 new gaskets, and connect the 2 No.3 air tubes
with the 4 bolts to the No.2 air switching valve.
Torque: 10 N´m (102 kgf´cm, 7 ft´lbf)
(d) Install the 2 new gaskets, and connect the 2 No.3 air
tubes with the 4 nuts to the exhaust manifold.
Torque: 10 N´m (102 kgf´cm, 7 ft´lbf)
3. INSTALL AIR PUMP ASSEMBLY
(a) Install the air pump assembly with the 4 bolts.
Torque: 16 N´m (163 kgf´cm, 12 ft´lbf)
(b) Connect the pressure sensor connector for the air injec-
tion system.
(c) Connect the air switching valve connector.
(d) Connect the air hose No.2 to the air switching valve.
4. INSTALL VSV FOR AIR INJECTION SYSTEM
(a) Install the 2 VSVs with the 2 bolts to the intake manifold.
Torque: 7.5 N´m (76 kgf´cm, 66 in.´lbf)
(b) Connect the 2 vacuum hoses to the 2 VSVs.
5. INSTALL INTAKE MANIFOLD (See page EM±60)
6. INSTALL THROTTLE BODY COVER

SF1XD±01
± SFISFI SYSTEM
SF±1
2735 Author: Date:
2005 SEQUOIA (RM1146U)
SFI SYSTEM
PRECAUTION
HINT:
All DTCs retained in the ECM will be erased when the negative
(±) terminal cable is removed from the battery.
If necessary, read the DTC before removing the negative (±)
terminal cable from the battery.
1. BEFORE WORKING ON FUEL SYSTEM,
DISCON-
NECT CABLE FROM NEGATIVE (±) BATTERY TERMI-
NAL
2. DO NOT SMOKE OR WORK NEAR AN OPEN FLAME
WHEN WORKING ON FUEL SYSTEM
3. KEEP GASOLINE AWAY FROM RUBBER OR
LEATH-
ER PARTS
4. MAINTENANCE PRECAUTIONS
(a) To prevent engine misfire, these precautions should be
taken.
(1) Check the battery terminals are proper connected.
(2) After repair, check that the ignition coil terminals
and all other ignition system lines are reconnected
securely.
(3) When cleaning the engine compartment, be espe-
cially careful to protect the electrical system from
water.
(b) Observe the following when handling the air fuel ratio
sensors and oxygen sensor.
(1) Do not drop the sensor or hit it against another ob-
ject.
(2) The sensor should be free from any contact with wa-
ter.
5. IF VEHICLE IS EQUIPPED WITH MOBILE RA-
DIO
SYSTEM (HAM, CB, ETC.)
If the vehicle is equipped with a mobile communication system,
refer to the precaution in the IN section.
6. AIR INDUCTION SYSTEM
(a) Removal of the engine oil dipstick, oil filler cap, PCV hose,
may break the engine.
(b) Disconnection, looseness or cracks in the parts of the air
induction system between the throttle body and cylinder
head may result in air suction and break the engine.
7. ELECTRONIC CONTROL SYSTEM
(a) Before removing SFI wiring connectors, terminals, first
disconnect the power by turning the ignition switch off or
disconnecting the negative (±) terminal cable from the
battery.
HINT:
Be sure to check DTCs before disconnecting the negative (±)
terminal cable from the battery.

B17467
SF1XJ±01
D13872
Hand±Held Tester
DLC3
CAN VIM
± SFITHROTTLE BODY
SF±39
2773 Author: Date:
2005 SEQUOIA (RM1146U)
THROTTLE BODY
ON±VEHICLE INSPECTION
1. REMOVE THROTTLE BODY COVER
2. INSPECT SYSTEM OPERATION
(a) Inspect the throttle control motor for operating sound.
(1) Turn the ignition switch ON.
(2) When depressing the accelerator pedal, check the
running sound of the motor. Also, check that there
is no friction sound.
If operation is not as specified, check the throttle control motor
(see step 3), wiring and ECM.
(b) Inspect the accelerator pedal position sensor.
(1) Connect a hand±held tester to the Controller Area
Network Vehicle Interface Module (CAN VIM). Then
connect the CAN VIM to the Date Link Connector 3
(DLC3).
(2) Check that the MIL does not light up.
(3) When turning the accelerator pedal position sensor
lever to the full±open position, check that the
throttle valve opening percentage (THROTTLE
POS) of the CURRENT DATA showns the standard
value.
Standard throttle valve opening percentage:
60% or more
If operation is not as specified, check that the accelerator pedal
position sensor (see page DI±370), wiring and ECM.
If not using a hand±held tester, measure the voltage between
terminals (VTA1±E2, VTA2±E2) of the ECM connector (See
page DI±127).
(c) Inspect the idle speed.
(1) Start the engine and check that the MIL does not
light up.
(2) Allow the engine to warm up to normal operating
temperature.
(3) Turn the A/C compressor ON to OFF, and check the
idle speed.
Idle speed (Transmission in neutral): 700 ± 50 rpm
NOTICE:
Perform inspection without an electrical load.
(d) After checking the above (a) to (c), perform the driving test
and check that there is no sense of incongruity.

B17499
M±
M+
Ohmmeter SF±40
± SFITHROTTLE BODY
2774 Author: Date:
2005 SEQUOIA (RM1146U)
3. INSPECT THROTTLE CONTROL MOTOR
(a) Disconnect the throttle control motor connector.
(b) Using an ohmmeter, measure the motor resistance be-
tween terminals M+ and M±.
Motor resistance: 0.3 to 100 W at 20°C (68°F)
If the resistance is not as specified, replace the throttle body as-
sembly (see page SF±42).
(c) Reconnect the throttle control motor connector.
4. INSPECT THROTTLE POSITION SENSOR
(See page DI±127)
If necessary, replace the throttle body assembly (see page
SF±42).
5. REINSTALL THROTTLE BODY COVER

SF1XR±01
S04947
Continuity
Ohmmeter
Ohmmeter
No Continuity 12
35
S04946
BatteryOhmmeter
Continuity 12
35
± SFIA/F SENSOR HEATER RELAY
SF±57
2791 Author: Date:
2005 SEQUOIA (RM1146U)
A/F SENSOR HEATER RELAY
INSPECTION
1. REMOVE RELAY BOX COVER
2. REMOVE A/F SENSOR HEATER RELAY (Marking: A/F
HTR)
3. INSPECT A/F SENSOR HEATER RELAY CONTINUITY
(a) Using an ohmmeter, check that there is continuity be-
tween terminals 1 and 2.
If there is no continuity, replace the relay.
(b) Check that there is no continuity between terminals 3 and
5.
If there is continuity, replace the relay.
4. INSPECT A/F SENSOR HEATER RELAY OPERATION
(a) Apply battery voltage across terminals 1 and 2.
(b) Using an ohmmeter, check that there is continuity be-
tween terminals 3 and 5.
If there is no continuity, replace the relay.
5. REINSTALL A/F SENSOR HEATER RELAY
6. REINSTALL RELAY BOX COVER

SF0PN±14
B17471
PS Air Hose
PCV Hose
Intake Air Connector

GasketECT Sensor
Connector
ECT Sensor
N´m (kgf´cm, ft´lbf) : Specified torque

Non±reusable part
Vacuum HoseThrottle Body Cover
MAF Meter Wire
Suction Hose
20 (204, 15)
SF±64
± SFIENGINE COOLANT TEMPERATURE (ECT) SENSOR
2798 Author: Date:
2005 SEQUOIA (RM1146U)
ENGINE COOLANT TEMPERATURE (ECT) SENSOR
COMPONENTS

SF0PO±19
B02308
S01196S01699Z17274
Ohmmeter
Resistance kW
Temperature °C (°F) Acceptable 30
20
10
5
3
2
1
0.5
0.3
0.2
0.1
40 ±20 0 20 60 80 100
(212) (176) (140) (104) (68) (32) (±4)
± SFIENGINE COOLANT TEMPERATURE (ECT) SENSOR
SF±65
2799 Author: Date:
2005 SEQUOIA (RM1146U)
INSPECTION
1. DRAIN ENGINE COOLANT
2. REMOVE THROTTLE BODY COVER
3. REMOVE INTAKE AIR CONNECTOR
4. DISCONNECT THROTTLE BODY FROM INTAKE MAN-
IFOLDS
Remove the nut and 3 bolts, and disconnect the throttle body
from the intake manifold.
5. REMOVE ECT SENSOR
(a) Disconnect the ECT sensor connector.
(b) Remove the ECT sensor and gasket.
6. INSPECT ECT SENSOR
Using an ohmmeter, measure the resistance between the ter-
minals.
Resistance: Refer to the graph
If the resistance is not as specified, replace the ECT sensor.
7. REINSTALL ECT SENSOR
(a) Install a new gasket and the ECT sensor.
Torque: 19.6 N´m (200 kgf´cm, 14 ft´lbf)
(b) Connect the ECT sensor connector.
8. REINSTALL THROTTLE BODY TO INTAKE MAN-
IFOLDS
Install a new gasket and the throttle body with the 2 bolts and
2 nuts.
Torque: 20 N´m (204 kgf´cm, 15 ft´lbf)
9. REINSTALL INTAKE AIR CONNECTOR
10. REFILL WITH ENGINE COOLANT (See page CO±2)
11. REINSTALL THROTTLE BODY COVER