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Diagnostic ProcedureNBS001NO
PROCEDURE FOR MALFUNCTION A
1. CHECK GROUND CONNECTIONS
Models with VDC system, navigation system or telephone
1. Turn ignition switch OFF.
2. Loosen and retighten ground screws on the body. Refer to EC-150, "
Ground Inspection" .
Models without VDC system, navigation system and telephone
1. Turn ignition switch OFF.
2. Loosen and retighten ground screws on the body. Refer to EC-150, "
Ground Inspection" .
OK or NG
OK >> GO TO 2.
NG >> Repair or replace ground connections.
1. Body ground E17 2. Body ground E43 3. Body ground B102
:Vehicle front
1. Body ground E17 2. Body ground E43 3. Body ground F152
(Passenger side view with dash side
finisher removed)
:Vehicle front
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2. CHECK HO2S2 GROUND CIRCUIT FOR OPEN AND SHORT
1. Disconnect heated oxygen sensor 2 harness connector.
2. Disconnect ECM harness connector.
3. Check harness continuity between HO2S2 terminal 1 and ECM terminal 84.
Refer to Wiring Diagram.
4. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 3.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
3. CHECK HO2S2 INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Check harness continuity between ECM terminal and HO2S2 terminal as follows.
Refer to Wiring Diagram.
2. Check harness continuity between the following terminals and ground.
Refer to Wiring Diagram.
3. Also check harness for short to power.
OK or NG
OK >> GO TO 4.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
1. Heated oxygen sensor 2 (bank 2) 2. Heated oxygen sensor 2 (bank 2)
harness connector3. Heated oxygen sensor 2 (bank 1)
4. Heated oxygen sensor 2 (bank 1)
harness connector
:Vehicle front
Continuity should exist.
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DTCTerminals
Bank
ECM Sensor
P0138 76 4 1
P0158 80 4 2
Continuity should exist.
DTCTerminals
Bank
ECM Sensor
P0138 76 4 1
P0158 80 4 2
Continuity should not exist.
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4. CHECK HO2S2 CONNECTOR FOR WATER
Check connectors for water.
OK or NG
OK >> GO TO 5.
NG >> Repair or replace harness or connectors.
5. CHECK HEATED OXYGEN SENSOR 2
Refer to EC-296, "
Component Inspection" .
OK or NG
OK >> GO TO 6.
NG >> Replace malfunctioning heated oxygen sensor 2.
6. CHECK INTERMITTENT INCIDENT
Refer to EC-141, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>>INSPECTION END Water should not exist.
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PROCEDURE FOR MALFUNCTION B
1. CHECK GROUND CONNECTIONS
Models with VDC system, navigation system or telephone
1. Turn ignition switch OFF.
2. Loosen and retighten ground screws on the body. Refer to EC-150, "
Ground Inspection" .
Models without VDC system, navigation system and telephone
1. Turn ignition switch OFF.
2. Loosen and retighten ground screws on the body. Refer to EC-150, "
Ground Inspection" .
OK or NG
OK >> GO TO 2.
NG >> Repair or replace ground connections.
1. Body ground E17 2. Body ground E43 3. Body ground B102
:Vehicle front
1. Body ground E17 2. Body ground E43 3. Body ground F152
(Passenger side view with dash side
finisher removed)
:Vehicle front
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2. CLEAR THE SELF-LEARNING DATA
With CONSULT-III
1. Start engine and warm it up to normal operating temperature.
2. Select “SELF-LEARNING CONT” in “WORK SUPPORT” mode with CONSULT-III.
3. Clear the self-learning control coefficient by touching “CLEAR”.
4. Run engine for at least 10 minutes at idle speed.
Is the 1st trip DTC P0172 or P0175 detected?
Is it difficult to start engine?
Without CONSULT-III
1. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch OFF.
3. Disconnect mass air flow sensor (bank 1) harness connector, and restart and run engine for at least 5 sec-
onds at idle speed.
4. Stop engine and reconnect mass air flow sensor (bank 1) harness connector.
5. Make sure DTC P0102 is displayed.
6. Erase the DTC memory. Refer to EC-61, "
HOW TO ERASE EMISSION-RELATED DIAGNOSTIC INFOR-
MATION" .
7. Make sure DTC P0000 is displayed.
8. Run engine for at least 10 minutes at idle speed.
Is the 1st trip DTC P0172 or P0175 detected?
Is it difficult to start engine?
Ye s o r N o
Yes >> Perform trouble diagnosis for DTC P0172, P0175. Refer to EC-334, "DTC P0172, P0175 FUEL
INJECTION SYSTEM FUNCTION" .
No >> GO TO 3.
1. Mass air flow sensor (with intake air
temperature sensor) (bank 1)2. Mass air flow sensor (with intake air
temperature sensor) (bank 2)
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3. CHECK HO2S2 GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect heated oxygen sensor 2 harness connector.
3. Disconnect ECM harness connector.
4. Check harness continuity between HO2S2 terminal 1 and ECM terminal 84.
Refer to Wiring Diagram.
5. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 4.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
4. CHECK HO2S2 INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Check harness continuity between ECM terminal and HO2S2 terminal as follows.
Refer to Wiring Diagram.
2. Check harness continuity between the following terminals and ground.
Refer to Wiring Diagram.
3. Also check harness for short to power.
OK or NG
OK >> GO TO 5.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
1. Heated oxygen sensor 2 (bank 2) 2. Heated oxygen sensor 2 (bank 2)
harness connector3. Heated oxygen sensor 2 (bank 1)
4. Heated oxygen sensor 2 (bank 1)
harness connector
:Vehicle front
Continuity should exist.
PBIB3502E
DTCTerminals
Bank
ECM Sensor
P0138 76 4 1
P0158 80 4 2
Continuity should exist.
DTCTerminals
Bank
ECM Sensor
P0138 76 4 1
P0158 80 4 2
Continuity should not exist.
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5. CHECK HEATED OXYGEN SENSOR 2
Refer to EC-296, "
Component Inspection" .
OK or NG
OK >> GO TO 6.
NG >> Replace malfunctioning heated oxygen sensor 2.
6. CHECK INTERMITTENT INCIDENT
Refer to EC-141, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>>INSPECTION END
Component InspectionNBS0006P
HEATED OXYGEN SENSOR 2
With CONSULT-III
1. Turn ignition switch ON and select “DATA MONITOR” mode with CONSULT-III.
2. Start engine and warm it up to the normal operating temperature.
3. Turn ignition switch OFF and wait at least 10 seconds.
4. Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load.
5. Let engine idle for 1 minute.
6. Select “FUEL INJECTION” in “ACTIVE TEST” mode, and select “HO2S2 (B1)/(B2)” as the monitor item
with CONSULT-III.
7. Check “HO2S2 (B1)/(B2)” at idle speed when adjusting “FUEL INJECTION” to ±25%.
“HO2S2 (B1)/(B2)” should be above 0.68V at least once when the “FUEL INJECTION” is +25%.
“HO2S2 (B1)/(B2)” should be below 0.18V at least once when the “FUEL INJECTION” is −25%.
CAUTION:
Discard any heated oxygen sensor which has been dropped from a height of more than 0.5 m (19.7
in) onto a hard surface such as a concrete floor; use a new one.
Before installing new oxygen sensor, clean exhaust system threads using Oxygen Sensor Thread
Cleaner tool J-43897-18 or J-43897-12 and approved anti-seize lubricant.
Without CONSULT-III
1. Start engine and warm it up to the normal operating temperature.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load.
4. Let engine idle for 1 minute.
5. Set voltmeter probes between ECM terminal 76 [HO2S2 (B1) signal] or 80 [HO2S2 (B2) signal] and
ground.
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6. Check the voltage when revving up to 4,000 rpm under no load
at least 10 times.
(Depress and release accelerator pedal as soon as possible.)
The voltage should be above 0.68V at least once during this
procedure.
If the voltage is above 0.68V at step 6, step 7 is not neces-
sary.
7. Keep vehicle at idling for 10 minutes, then check voltage. Or
check the voltage when coasting from 80 km/h (50 MPH) in D
position (A/T), 4th gear position (M/T).
The voltage should be below 0.18V at least once during this
procedure.
8. If NG, replace heated oxygen sensor 2.
CAUTION:
Discard any heated oxygen sensor which has been dropped from a height of more than 0.5 m (19.7
in) onto a hard surface such as a concrete floor; use a new one.
Before installing new oxygen sensor, clean exhaust system threads using Oxygen Sensor Thread
Cleaner tool J-43897-18 or J-43897-12 and approved anti-seize lubricant.
Removal and InstallationNBS0006Q
HEATED OXYGEN SENSOR 2
Refer to EM-22, "EXHAUST MANIFOLD AND THREE WAY CATALYST" .
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