CHECK HARNESS AND CONNECTOR (AIR FUEL RATIO SENSOR - ECM)
CHECK WHETHER DTC OUTPUT RECURS
DTC P2237 Oxygen (A/F) Sensor Pumping Current Circuit / Open (Bank 1 Sensor 1) |
DTC P2238 Oxygen (A/F) Sensor Pumping Current Circuit Low (Bank 1 Sensor 1) |
DTC P2239 Oxygen (A/F) Sensor Pumping Current Circuit High (Bank 1 Sensor 1) |
DTC P2252 Oxygen (A/F) Sensor Reference Ground Circuit Low (Bank 1 Sensor 1) |
DTC P2253 Oxygen (A/F) Sensor Reference Ground Circuit High (Bank 1 Sensor 1) |
DESCRIPTION
Refer to DTC P2195 (LandCruiser RM000000WC40YKX_01.html).| DTC No. | DTC Detection Condition | Trouble Area |
| P2237 | Open in the circuit between terminals AF+ and AF- of the air fuel ratio sensor while the engine is running (2 trip detection logic). |
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| P2238 |
(a) AF+ voltage is 0.5 V or less. (b) (AF+) - (AF-) is 0.1 V or less.
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| P2239 | AF+ voltage is higher than 4.5 V for 5.0 seconds or more (2 trip detection logic). |
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| P2252 | AF- voltage is 0.5 V or less for 5.0 seconds or more (2 trip detection logic). |
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| P2253 | AF- voltage is higher than 4.5 V for 5.0 seconds or more (2 trip detection logic). |
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MONITOR DESCRIPTION
These DTCs are output when there is an open or short in the air fuel ratio sensor circuit, or if the air fuel ratio sensor output drops.To detect these problems, the voltage of the air fuel ratio sensor is monitored when turning the ignition switch to ON, and the admittance (admittance is an electrical term that indicates the ease of flow of current) is checked while driving. If the voltage of the air fuel ratio sensor is between 0.5 V and 4.5 V, it is considered normal. If the voltage is outside of the specified range, or the admittance is below the standard value, the ECM will determine that there is a malfunction in the air fuel ratio sensor. If the same malfunction is detected in the next driving cycle, the MIL is illuminated and a DTC is stored.
The air fuel ratio sensor varies its output voltage in proportion to the air-fuel ratio. If the air fuel ratio sensor impedance (alternating current resistance) or output voltage deviates greatly from the standard range, the ECM determines that there is an open or short in the air fuel ratio sensor circuit.
MONITOR STRATEGY
| Required Sensors/Components | Air fuel ratio sensor |
| Frequency of Operation | Continuous |
CONFIRMATION DRIVING PATTERN
- Connect the GTS to the DLC3.
- Turn the ignition switch to ON and turn the GTS on.
- Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).
- Turn the ignition switch off and wait for at least 30 seconds.
- Turn the ignition switch to ON and turn the GTS on.
- Start the engine.
- Idle the engine for 5 minutes or more.
- Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.
- Read the pending DTCs.
- HINT:
- If a pending DTC is output, the system is malfunctioning.
- If a pending DTC is not output, perform the following procedure.
- Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.
- Input the DTC: P2237, P2238, P2239, P2252 or P2253
- Check the DTC judgment result.
GTS Display Description NORMAL - DTC judgment completed
- System normal
ABNORMAL - DTC judgment completed
- System abnormal
INCOMPLETE - DTC judgment completed
- Perform driving pattern after confirming DTC enabling conditions
N/A - Unable to perform DTC judgment
- Number of DTCs which do not fulfill DTC preconditions has reached ECU memory limit
- HINT:
- If the judgment result shows NORMAL, the system is normal.
- If the judgment result shows ABNORMAL, the system has a malfunction.
- If the judgment result shows INCOMPLETE or N/A, perform the Confirmation Driving Pattern and check the DTC judgment result again.
- DTC judgment completed
WIRING DIAGRAM
Refer to DTC P2195 (LandCruiser RM000000WC40YKX_07.html).INSPECTION PROCEDURE
- HINT:
- Read freeze frame data using the GTS. Freeze frame data records the engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, and other data from the time the malfunction occurred.
- Sensor 1 refers to the sensor closest to the engine assembly.
- Sensor 2 refers to the sensor farthest away from the engine assembly.
| 1.CHECK HARNESS AND CONNECTOR (AIR FUEL RATIO SENSOR - ECM) |
Disconnect the air fuel ratio sensor connector.
Disconnect the ECM connector.
Measure the resistance according to the value(s) in the table below.
- Standard Resistance:
Tester Connection Condition Specified Condition C56-1 (HA1A) - C154-6 (HA1A) Always Below 1 Ω C56-3 (A1A+) - C154-26 (A1A+) Always Below 1 Ω C56-4 (A1A-) - C154-34 (A1A-) Always Below 1 Ω C56-1 (HA1A) or C154-6 (HA1A) - Body ground Always 10 kΩ or higher C56-3 (A1A+) or C154-26 (A1A+) - Body ground Always 10 kΩ or higher C56-4 (A1A-) or C154-34 (A1A-) - Body ground Always 10 kΩ or higher
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| OK | |
| 2.REPLACE AIR FUEL RATIO SENSOR |
Replace the air fuel ratio sensor (LandCruiser RM00000175900NX.html).
- HINT:
- Perform "Inspection After Repair" after replacing the air fuel ratio sensor (LandCruiser RM000004NJC03XX.html).
| NEXT | |
| 3.CHECK WHETHER DTC OUTPUT RECURS |
Connect the GTS to the DLC3.
Turn the ignition switch to ON.
Turn the GTS on.
Clear the DTCs (LandCruiser RM000000VNG00DX.html).
Turn the ignition switch off and wait for at least 30 seconds.
Start the engine.
Allow the engine to idle for 5 minutes or more.
Enter the following menus: Powertrain / Engine and ECT / Trouble Codes / Pending.
Read the pending DTCs.
Result Result Proceed to No DTC is output A P2237, P2238, P2239, P2252 or P2253 is output B
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| A | ||
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