P0154
DTC P0154: Heated Oxygen Sensor No Activity Detected (bank 2, sensor 1)HEATED OXYGEN SENSOR CIRCUIT NO ACTIVITY DETECTED (bank 2, sensor 1) CIRCUIT
- Refer to DTC P0152 - Heated Oxygen Sensor Circuit High Voltage (bank 2, sensor 1).
- Refer to DTC P0202, P0204, P0206 - Injector Circuit.
CIRCUIT OPERATION
- Refer to DTC P0152 - Heated Oxygen Sensor Circuit High Voltage (bank 2, sensor 1).
- Refer to DTC P0202, P0204, P0206 - Injector Circuit.
TECHNICAL DESCRIPTION
- The ECM
- If the left bank heated oxygen sensor (front) has deteriorated, corrections will be made by the left bank heated oxygen sensor (rear).
- DTC P0154 is stored when abnormality of the air/fuel ratio feed back control system is detected.
DESCRIPTIONS OF MONITOR METHODS
Left bank heated oxygen sensor (front) output voltage does not cross 0.5 volt within specified period.
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)
- Misfire monitor
Sensor (The sensor below is determined to be normal)
- Volume airflow sensor
- Engine coolant temperature sensor
- Intake air temperature sensor
- Barometric pressure sensor
- Throttle position sensor
DTC SET CONDITIONS
Logic Flow Chart:
Logic Flow Chart
Check Conditions
- 20 seconds or more have passed since the starting sequence was completed.
- Engine coolant temperature is higher than 76 °C (169 °F).
- Engine speed is higher than 1,200 r/min.
- Volumetric efficiency is at between 30 and 95 percent.
- Throttle position sensor output voltage is lower then4 volts.
- Except while fuel is being shut off.
- Monitoring time: 30 seconds.
Judgment Criteria
- Light bank heated oxygen sensor (front) output voltage does not get across 0.5 volt within about 30 seconds.
OBD-II DRIVE CYCLE PATTERN
Refer to, Diagnostic Function - OBD-II Drive Cycle - Procedure 6 - Other Monitor. OBD-II Drive Cycle Pattern Lists
TROUBLESHOOTING HINTS (The most likely causes for this code to be set are:)
- Left bank heated oxygen sensor (front) deteriorated.
- Harness damage in left bank heated oxygen sensor (front) output line.
NOTE: When the left bank heated oxygen sensor (front) begins to deteriorate, the left bank heated oxygen sensor output voltage will deviate from the voltage when the sensor was new (normally 0.5 volt at stoichiometric ratio). This deviation will be corrected by the left bank heated oxygen sensor (rear).
If the left bank heated oxygen sensor (rear) responds poorly because it has deteriorated, it will improperly correct the left bank heated oxygen sensor (front). Thus, even when closed loop control is being effected, the fluctuation of the left bank heated oxygen sensor (front) output voltage decreases, without intersecting with 0.5 volt. As a result, there is a possibility of DTC P0154 becoming registered.
- ECM failed.
- PCM failed.
- Connector damage.
- Exhaust leak.
- Vacuum leak.
- Injector damage. Fuel pressure.
DIAGNOSIS
Required Special Tools:
- MB991958: Scan Tool (MUT-III Sub Assembly)
- MB991824: V.C.I.
- MB991827: USB Cable
- MB991911: Main Harness B
- MB998464: Test Harness
STEP 1. Using scan tool MB991958, check data list item 59: Heated Oxygen Sensor Bank 2, Sensor 2 (left rear).
CAUTION: To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991958.
1. Connect scan tool MB991958 to the data link connector.
2. Start the engine and run at idle.
3. Set scan tool MB991958 to the data reading mode for item 59, Heated Oxygen Sensor Bank 2, Sensor 2 (left rear).
- Warming up the engine. When the engine is revved, the output voltage should repeat 0 volt and 0.6 to 1.0 volt alternately.
4. Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the sensor operating properly?
YES: Go to Step 2.
NO: Refer to, DTC P0157 - Heated Oxygen Sensor Circuit Low Voltage (bank 2, sensor 2), DTC P0158 - Heated Oxygen Sensor Circuit High Voltage (bank 2, sensor 2), DTC P0159 - Heated Oxygen Sensor Circuit Slow Response (bank 2, sensor 2).
STEP 2. Check the exhaust leaks.
Q: Are there any abnormalities?
YES: Go to Step 3.
NO: Repair it. Then go to Step 12.
STEP 3. Check the intake system vacuum leak.
Q: Are there any abnormalities?
YES: Go to Step 4.
NO: Repair it. Then go to Step 12.
STEP 4. Check connector B-24 at the left bank heated oxygen sensor (front) for damage.
Q: Is the connector in good condition?
YES: Go to Step 5.
NO: Repair or replace it. Refer to Harness Connector Inspection. Then go to Step 12.
STEP 5. Check the left bank heated oxygen sensor (front).
1. Disconnect the left bank heated oxygen sensor (front) connector B-24 and connect test harness special tool MD998464 to the connector on the left bank heated oxygen sensor (front) side.
2. Warm up the engine until engine coolant 80 °C (176 °F) or higher.
CAUTION: Be very careful when connecting the jumper wires; incorrect connection can damage the left bank heated oxygen sensor (front).
3. Use the jumper wires to connect terminal 1 (red clip) to the positive battery terminal and terminal 3 (blue clip) to the negative battery terminal.
4. Connect a digital volt meter between terminal 2 (black clip) and terminal 4 (white clip).
5. While repeatedly revving the engine, measure the left bank heated oxygen sensor (front) output voltage.
Standard value: 0.6 - 1.0 volt
Q: Is the voltage between 0.6 and 1.0 volt?
YES: Go to Step 6.
NO: Replace the left bank heated oxygen sensor (front). Then go to Step 12.
STEP 6. Check connector B-02, B-06, B-25 at left bank injector for damage.
Q: Is the connector in good condition?
YES: Go to Step 7.
NO: Repair or replace it. Refer to Harness Connector Inspection. Then go to Step 12.
STEP 7. Check the left bank injector.
1. Disconnect the left bank injector connector B-02, B-06, B-25.
2. Measure the resistance between each injector side connector terminal No. 1 and No. 2.
Standard value: 13 - 16 Ohms [at 20 °C (68 °F)]
Q: Is the resistance between 13 and 16 Ohms?
YES: Go to Step 8.
NO: Replace the faulty injector. Then go to Step 12.
STEP 8. Check connector C-51, C-62 at ECM
Q: Is the connector in good condition?
YES: Go to Step 9.
NO: Repair or replace it. Refer to Harness Connector Inspection. Then go to Step 12.
STEP 9. Check for harness damage between left bank heated oxygen sensor (front) connector B-24 (terminal No. 4) and ECM connector C-62 (terminal No. 71)
Q: Is the harness wire in good condition?
YES: Go to Step 10.
NO: Repair it. Then go to Step 12.
STEP 10. Check for harness damage between left bank injector connector and ECM connector
a. Check the harness wire between injector connector B-02 (terminal No. 2) and ECM connector C-51 (terminal No. 9)
b. Check the harness wire between injector connector B-06 (terminal No. 2) and ECM connector C-51 (terminal No. 2)
c. Check the harness wire between injector connector B-25 (terminal No. 2) and ECM connector C-51 (terminal No. 25)
Q: Is the harness wire in good condition?
YES: Go to Step 11.
NO: Repair it. Then go to Step 12.
STEP 11. Check the fuel pressure.
Refer to On-vehicle Service - Fuel Pressure Test.
Q: Is the fuel pressure normal?
YES: Replace the ECM or PCM. Then go to Step 12.
NO: Repair or replace it. Then go to Step 12.
STEP 12. Test the OBD-II drive cycle.
1. Carry out a test drive with the drive cycle pattern. Refer to Diagnostic Function - OBD-II Drive Cycle - Procedure 6 - Other Monitor. OBD-II Drive Cycle Pattern Lists
2. Check the diagnostic trouble code (DTC).
Q: Is DTC P0154 set?
YES: Retry the troubleshooting.
NO: The inspection is complete.