Nissan Frontier. Instruction — part 410
P0138 HO2S2
EC-211
< DTC/CIRCUIT DIAGNOSIS >
[QR25DE]
C
D
E
F
G
H
I
J
K
L
M
A
EC
N
P
O
P0138 HO2S2
Component Description
INFOID:0000000009480871
The heated oxygen sensor 2, after three way catalyst (manifold),
monitors the oxygen level in the exhaust gas.
Even if switching characteristics of the A/F sensor 1 are shifted, the
air-fuel ratio is controlled to stoichiometric, by the signal from the
heated oxygen sensor 2.
This sensor is made of ceramic zirconia. The zirconia generates volt-
age from approximately 1V in richer conditions to 0V in leaner condi-
tions.
Under normal conditions the heated oxygen sensor 2 is not used for
engine control operation.
On Board Diagnosis Logic
INFOID:0000000009480872
The heated oxygen sensor 2 has a much longer switching time between rich and lean than the air fuel ratio (A/
F) sensor 1. The oxygen storage capacity of the three way catalyst (manifold) causes the longer switching
time.
MALFUNCTION A
To judge the malfunctions of heated oxygen sensor 2, ECM monitors
whether the voltage is unusually high during various driving condi-
tions such as fuel cut.
MALFUNCTION B
To judge the malfunctions of heated oxygen sensor 2, ECM monitors
whether the minimum voltage of sensor is sufficiently low during var-
ious driving conditions such as fuel cut.
SEF327R
PBIB1848E
PBIB2376E
DTC No.
Trouble diagnosis name
DTC detecting condition
Possible cause
P0138
0138
Heated oxygen sensor 2
circuit high voltage
A)
An excessively high voltage from the sensor
is sent to ECM.
• Harness or connectors
(The sensor circuit is open or shorted)
• Heated oxygen sensor 2
B)
The minimum voltage from the sensor is not
reached to the specified voltage.
• Harness or connectors
(The sensor circuit is open or shorted)
• Heated oxygen sensor 2
• Fuel pressure
• Fuel injector
EC-212
< DTC/CIRCUIT DIAGNOSIS >
[QR25DE]
P0138 HO2S2
DTC Confirmation Procedure
INFOID:0000000009480873
Perform PROCEDURE FOR MALFUNCTION A first.
If DTC cannot be confirmed, perform PROCEDURE FOR MALFUNCTION B.
NOTE:
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
PROCEDURE FOR MALFUNCTION A
With CONSULT
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 2 minutes.
5. Check 1st trip DTC.
6. If 1st trip DTC is detected, go to
With GST
Follow the procedure “WITH CONSULT” above.
PROCEDURE FOR MALFUNCTION B
With CONSULT
TESTING CONDITION:
For better results, perform DTC WORK SUPPORT at a temperature of 0 to 30
°C (32 to 86 °F).
1. Turn ignition switch ON and select “DATA MONITOR” mode with CONSULT.
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. Make sure that “COOLAN TEMP/S” indicates more than 70
°C (158°F).
If not, warm up engine and go to next step when “COOLAN TEMP/S” indication reaches 70
°C (158°F).
7. Open engine hood.
8. Select “HO2S2 (B1) P1146” of “HO2S2” in “DTC WORK SUPPORT” mode with CONSULT.
9. Start engine and following the instruction of CONSULT display.
NOTE:
It will take at most 10 minutes until “COMPLETED” is displayed.
10. Make sure that “OK” is displayed after touching “SELF-DIAG RESULTS”.
If “NG” is displayed, refer to
.
If “CAN NOT BE DIAGNOSED” is displayed, perform the following.
a. Turn ignition switch OFF and leave the vehicle in a cool place (soak the vehicle).
b. Return to step 1.
Overall Function Check
INFOID:0000000009480874
Use this procedure to check the overall function of the heated oxygen sensor 2 circuit. During this check, a 1st
trip DTC might not be confirmed.
PROCEDURE FOR MALFUNCTION B
With GST
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 33 (HO2S2 signal) and ground.
P0138 HO2S2
EC-213
< DTC/CIRCUIT DIAGNOSIS >
[QR25DE]
C
D
E
F
G
H
I
J
K
L
M
A
EC
N
P
O
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 0.78V and below 0.18V at least once during this procedure.
If the voltage can be confirmed in step 6, step 7 is not necessary.
7. Keep vehicle at idling for 10 minutes, then check the 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 above 0.78V and below 0.18V at least once during this procedure.
8. If NG, go to
Diagnosis Procedure
INFOID:0000000009480875
PROCEDURE FOR MALFUNCTION A
1.
CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten three ground screws on the body. Refer to
OK or NG
OK
>> GO TO 2.
NG
>> Repair or replace ground connections.
2.
CHECK HO2S2 CONNECTOR FOR WATER
1. Disconnect heated oxygen sensor 2 harness connector.
2. Check that water is not inside connectors.
OK or NG
OK
>> GO TO 3.
NG
>> Repair or replace harness or connectors.
3.
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 4 and ECM
terminal 35.
Refer to Wiring Diagram.
4. Also check harness for short to ground and short to power.
OK or NG
OK
>> GO TO 4.
NG
>> Repair open circuit, short to ground 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 33 and HO2S2 terminal 1.
Refer to Wiring Diagram.
2. Check harness continuity between ECM terminal 33 or HO2S2 terminal 1 and ground.
Refer to Wiring Diagram.
BBIA0614E
Continuity should exist.
BBIA0613E
Continuity should exist.
EC-214
< DTC/CIRCUIT DIAGNOSIS >
[QR25DE]
P0138 HO2S2
3. Also check harness for short to power.
OK or NG
OK
>> GO TO 5.
NG
>> Repair open circuit, short to ground or short to power in harness or connectors.
5.
CHECK HEATED OXYGEN SENSOR 2
EC-216, "Component Inspection"
OK or NG
OK
>> GO TO 6.
NG
>> Replace heated oxygen sensor 2. Refer to
.
6.
CHECK INTERMITTENT INCIDENT
GI-42, "Intermittent Incident"
.
>> INSPECTION END
PROCEDURE FOR MALFUNCTION B
1.
CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten three ground screws on the body. Refer to
OK or NG
OK
>> GO TO 2.
NG
>> Repair or replace ground connections.
2.
CLEAR THE SELF-LEARNING DATA
With CONSULT
1. Start engine and warm it up to normal operating temperature.
2. Select “SELF-LEARNING CONT” in “WORK SUPPORT” mode with CONSULT.
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 detected?
Is it difficult to start engine?
Without CONSULT
1. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch OFF.
Continuity should not exist.
BBIA0614E
Нет комментариевНе стесняйтесь поделиться с нами вашим ценным мнением.
Текст