P0140
DTC P0140: Heated Oxygen Sensor Circuit No Activity Detected (bank 1, sensor 2)Right Bank Heated Oxygen Sensor (rear) Circuit:
CIRCUIT OPERATION
- A voltage corresponding to the oxygen concentration in the exhaust gas is sent to the ECM
- Terminal No. 2 of the right bank heated oxygen sensor (rear) is grounded with ECM
- The ECM
TECHNICAL DESCRIPTION
- The output signal of the right bank heated oxygen sensor (front) is compensated by the output signal of the right bank heated oxygen sensor (rear).
- The ECM
DESCRIPTIONS OF MONITOR METHODS
Right bank heated oxygen sensor (rear) output voltage does not change during specified.
MONITOR EXECUTION
Continuous
MONITOR EXECUTION CONDITIONS (Other monitor and Sensor)
Other Monitor (There is no temporary DTC stored in memory for the item monitored below)
- Heated oxygen sensor heater (front) monitor
- Heated oxygen sensor heater (rear) monitor
- Air/fuel ratio feedback monitor
Sensor (The sensor below is determined to be normal)
- Mass airflow sensor
- Engine coolant temperature sensor
- Intake air temperature sensor
- Barometric pressure sensor
DTC SET CONDITIONS
Logic Flow Chart:
Logic Flow Chart
Check Conditions
- Engine coolant temperature is higher than 76 degrees C (169 degrees F).
- The right bank heated oxygen sensor (front) is active.
- The cumulative mass airflow sensor output is higher than 1638 g.
- Repeat 3 or more times: drive*1, stop*2.
Drive*1:
- Engine speed is higher than 1,500 r/min.
- Volumetric efficiency is higher than 40 percent.
- Vehicle speed is higher than 30 km/h (19 mph).
- A total of more than 10 seconds have elapsed with the above mentioned conditions, and more than 2 seconds have elapsed with the fuel shut off.
Stop*2:
- Vehicle speed is lower than 1.5 km/h (1.0 mph).
Judgement Criterion
- Change in the output voltage of the right bank heated oxygen sensor (rear) is lower than 0.313 volt.
NOTE: Monitoring stops after fuel has been shut off for more than 41 seconds.
OBD-II DRIVE CYCLE PATTERN
Refer to Diagnostic Function - OBD-II Drive Cycle - Pattern 13. OBD-II Drive Cycle Pattern Lists
TROUBLESHOOTING HINTS (The most likely causes for this code to be set are: )
- Right bank heated oxygen sensor (rear) failed.
- Connector damage.
- ECM failed.
- PCM failed.
DIAGNOSIS
Required Special Tools:
- MB991958: Scan Tool (MUT-III Sub Assembly)
- MB991824: V.C.I.
- MB991827: USB Cable
- MB991910: Main Harness A
STEP 1. Replace the right bank heated oxygen sensor (rear).
1. Replace the right bank heated oxygen sensor (rear).
2. Carry out a test drive with the drive cycle pattern. Refer to Diagnostic Function - OBD-II Drive Cycle - Pattern 13. OBD-II Drive Cycle Pattern Lists
3. Check the diagnostic trouble code (DTC).
Q: Is DTC P0140 set?
YES: Refer to, P0137 - Heated Oxygen Sensor Circuit Low Voltage (bank 1, sensor 2), DTC P0138 - Heated Oxygen Sensor Circuit High Voltage (bank 1, sensor 2).
NO: The inspection is complete.