DTC P0137 / P0138 / P0140
Precautions: General safety (00)
DTC Detecting Condition and Trouble Area
| DTC detecting condition | Trouble area |
|---|---|
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P0137: O2 Sensor Circuit Low Voltage (Sensor 2) Output voltage of HO2S-2 circuit is lower than 0.06 V for 25 sec. after warming up. (3 D/C detection logic) |
•HO2S-2 and/or its circuit
•HO2S-2 heater and/or its circuit •Exhaust system •Air intake system •Fuel system •ECM |
|
P0138: O2 Sensor Circuit High Voltage (Sensor 2) Output voltage of HO2S-2 signal circuit is higher than 3.50 V for 25 sec. (3 D/C detection logic) |
|
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P0140: O2 Sensor Circuit No Activity Detected (Sensor 2) Output voltage of HO2S-2 circuit stays between 1.25 to 3.50 V for 25 sec. (3 D/C detection logic) |
Circuit Diagram
| [A]: | ECM connector (View: [a]) | B1: | HO2S-2 heater power supply circuit | 2. | HO2S-2 |
| A1: | HO2S-1 heater power supply circuit | B2: | HO2S-2 signal circuit | 3. | ECM |
| A2: | HO2S-1 signal circuit | B3: | HO2S-2 ground circuit | 4. | Shield wire |
| A3: | HO2S-1 ground circuit | B4: | HO2S-2 heater drive circuit | ||
| A4: | HO2S-1 heater drive circuit | 1. | HO2S-1 |
DTC Confirmation Procedure
WARNING:
If you do not select a suitable route and take proper precautions when performing a road test, an accident can occur.
•Select a level road with no traffic to minimize the risk of accident.
•Perform the test extremely carefully.
•Perform the road test using 2 persons, a driver and a tester.
•Perform the test extremely carefully.
•Perform the road test using 2 persons, a driver and a tester.
NOTE:
•Check that the following condition is met in this “DTC Confirmation Procedure”.
—Battery voltage > 11 V
•Check that the following DTCs are not detected in this “DTC Confirmation Procedure”.
—HO2S-2 heater (P0036, P0037 and P0038)
1)Warm up engine to normal operating temperature.
2)Drive vehicle at 50 to 80 km/h (31 to 50 mile/h) constantly for 10 min. or more.
DTC Troubleshooting
| Step | Action | Yes | No |
|---|---|---|---|
| 1 |
Was “Engine and Emission Control System Check” performed?
|
Go to Step 2.
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| 2 |
DTC check
Is there any DTC(s) other than P0137, P0138 and P0140?
|
Go to troubleshooting for applicable DTC(s).
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Go to Step 3.
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| 3 |
HO2S-2 signal circuit and ground circuit check
1)With ignition “OFF”, disconnect “C01” and “E01” connectors of ECM and HO2S-2 connector.
2)Check for proper terminal connection to “C01” and “E01” connectors and HO2S-2 connector.
3)If connections are OK, check the following points.
•Resistance of “B2” and “B3” circuits: less than 1 Ω
•Resistance between each of “B2” and “B3” circuits and ground: infinity •Resistance between “B2” circuit terminal and other terminal at HO2S-2 connector: infinity •Resistance between “B3” circuit terminal and other terminal at HO2S-2 connector: infinity •Voltage of “B2” and “B3” circuits: approx. 0 V (When ignition is “ON”) Is check result OK?
|
Go to Step 4.
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Repair or replace defective wiring harness.
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| 4 |
Exhaust system and air intake system check
1)Check exhaust system and air intake system for clogging or leakage.
Is check result OK?
|
Go to Step 5.
|
Repair or replace defective part.
|
| 5 |
HO2S-2 heater circuit check
1)Check HO2S-2 heater circuits according to Step 2 – 3 under DTC P0036 / P0037 / P0038:K14C.
Is check result OK?
|
Go to Step 6.
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Repair or replace defective part.
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| 6 |
Fuel injector and its circuit check
1)Check fuel injector circuit.
2)Check fuel injectors.
Is check result OK?
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Go to Step 7.
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Faulty injector(s) or its circuit.
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| 7 |
DTC recheck
1)Replace HO2S-2.
2)Perform “DTC Confirmation Procedure” to check for DTCs.
Is DTC P0137, P0138 or P0140 still detected?
|
Replace ECM and recheck DTC.
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End.
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