P0134
DTC P0134: Heated Oxygen Sensor Circuit No Activity Detected (bank 1, sensor 1)Heated Oxygen Sensor Circuit No Activity Detected (bank 1, sensor 1) Circuit
Right Bank Heated Oxygen Sensor (Front) Circuit:
Injector Circuit-Cylinder 1 (Part 1):
Injector Circuit-Cylinder 1 (Part 2):
Injector Circuit-Cylinder 3 (Part 1):
Injector Circuit-Cylinder 3 (Part 2):
Injector Circuit-Cylinder 5 (Part 1):
Injector Circuit-Cylinder 5 (Part 2):
CIRCUIT OPERATION
Heated Oxygen Sensor Circuit Low Voltage (bank 1, sensor 1)
- A voltage corresponding to the oxygen concentration in the exhaust gas is sent to the ECM (terminal No. 54) from the output terminal (terminal No. 4) of the right bank heated oxygen sensor (front).
- Terminal No. 2 of the right bank heated oxygen sensor (front) is grounded with ECM (terminal No. 55).
- The ECM applies an offset voltage of 0.5 volt to terminal No. 2 of the right bank heated oxygen sensor (front)
Injector Circuit - Cylinder 1
- The injector power is supplied from the injector relay (terminal No. 3).
- The ECM controls the injector by turning the power transistor in the ECM "ON" and "OFF".
Injector Circuit - Cylinder 3
- The injector power is supplied from the injector relay (terminal No. 3).
- The ECM controls the injector by turning the power transistor in the ECM "ON" and "OFF".
Injector Circuit - Cylinder 5
- The injector power is supplied from the injector relay (terminal No. 3).
- The ECM controls the injector by turning the power transistor in the ECM "ON" and "OFF".
TECHNICAL DESCRIPTION
- The ECM effects air/fuel ratio feedback control in accordance with the signals from the right bank heater oxygen sensor (front).
- If the right bank heated oxygen sensor (front) has deteriorated, corrections will be made by the right bank heated oxygen sensor (rear).
- DTC P0134 becomes stored in memory if a failure is detected in the above air/fuel ratio feedback control system.
DESCRIPTIONS OF MONITOR METHODS
Right bank heated oxygen sensor (front) output voltage does not exceed lean/rich criteria (about 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)
- Mass airflow sensor
- Engine coolant temperature sensor
- Intake air temperature sensor
- Barometric pressure sensor
- Throttle position sensor
DTC SET CONDITIONS
Logic Flow Chart:
Check Conditions
- 20 seconds or more have passed since the engine starting sequence was completed.
- Engine coolant temperature is higher than 7 °C (45 °F).
- Engine speed is higher than 1,200 r/min.
- Volumetric efficiency is higher than 30 percent.
- Throttle position sensor output voltage is lower than 4 volts.
- Except while fuel is being shut off.
- Monitoring time: 30 seconds.
Judgement Criterion
- Right bank heated oxygen sensor (front) output voltage does not get across lean/rich criteria (about 0.5 volt) within about 30 seconds.
OBD-II DRIVE CYCLE PATTERN
Refer to MFI Diagnostic Function-OBD-II Drive Cycle-Pattern. OBD-II Drive Cycle
TROUBLESHOOTING HINTS (The most likely causes for this code to be set are:)
- Right bank heated oxygen sensor (front) deteriorated.
- Harness damage
NOTE: When the right bank heated oxygen sensor (front) begins to deteriorate, the 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 right bank heated oxygen sensor (rear).
If the right bank heated oxygen sensor (rear) responds poorly because it has deteriorated, it will improperly correct the right bank heated oxygen sensor (front). Thus, even when closed loop control is being effected, the fluctuation of the right bank heated oxygen sensor (front) output voltage decreases, without intersecting with 0.5 volt. As a result, there is a possibility of DTC P0134 becoming registered.
- Open circuit in right bank injector.
- Connector damage.
- Exhaust leak.
- Air drawn in from gaps in gasket, seals, etc.
- Incorrect fuel pressure.
- ECM failed.
DIAGNOSIS
Required Special Tools:
- MB991958: Scan Tool (M.U.T.-III Sub Assembly)
- MB991824: V.C.I.
- MB991827: USB Cable
- MB991910: Main Harness A
- MB991316: Test Harness
STEP 1. Using scan tool MB991958, check data list item AD: Heated Oxygen Sensor Bank 1, Sensor 2 (right 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 AD, Heated Oxygen Sensor Bank 1, Sensor 2 (right 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 : Then go to Step 2.
NO : Refer to MFI DTC P0137-Heated Oxygen Sensor Circuit Low Voltage (bank 1, sensor 2), P0137 DTC P0138-Heated Oxygen Sensor Circuit High Voltage (bank 1, sensor 2), P0138 DTC P0139-Heated Oxygen Sensor Circuit Slow Response (bank 1, sensor 2), P0139 DTC P0140-Heated Oxygen Sensor Circuit No Activity Detected (bank 1, sensor 2). P0140
STEP 2. Check harness connector B-03 at the right bank heated oxygen sensor (front) and harness connector B-10 at the ECM for damage.
Q: Is the harness connector in good condition?
YES : Go to Step 3.
NO : Repair or replace it. Refer to General (Electrical), Harness Connector Inspection. Then go to Step 14.
STEP 3. Check the right bank heated oxygen sensor (front).
1. Disconnect the right bank heated oxygen sensor (front) connector B-03 and connect test harness special tool, MB991316, to the connector on the right bank heated oxygen sensor (front) side.
2. Warm up the engine until engine coolant temperature reaches 80 °C (176 °F) or higher.
3. Rev the engine for 5 minutes or more with the engine speed of 4,500 r/min.
4. Connect a digital voltage meter between terminal No. 2 (black clip) and terminal No. 4 (white clip).
5. While repeatedly revving the engine, measure the right bank heated oxygen sensor (front) output voltage.
Standard value: 0.6-1.0 volts
CAUTION:
- Be very careful when connecting the jumper wires; incorrect connection can damage the heated oxygen sensor.
- Be careful the heater can be damaged if a voltage beyond 8 volts is applied to the heated oxygen sensor heater.
NOTE: If the temperature of sensing area does not reach the high temperature [of approximately 400 °C (752 °F) or more] even though the oxygen sensor is normal, the output voltage would be possibly low in spite of the rich air-fuel ratio. Therefore, if the output voltage is low, use a jumper wire to connect the terminal No. 1 (red clip) and the terminal No. 3 (blue clip) of the heated oxygen sensor with the positive terminal and the negative terminal of 8 volts power supply respectively, then check again.
Q: Is the voltage between 0.6 and 1.0 volts?
YES : Go to Step 4.
NO : Replace the right bank heated oxygen sensor (front). Then go to Step 14.
STEP 4. Check for harness between the right bank heated oxygen sensor (front) connector B-03 and the ECM connector B-10.
1. Disconnect the right bank heated oxygen sensor (front) connector B-03 and the ECM connector B-10.
2. Measure the resistance between the right bank heated oxygen sensor (front) connector B-03 and the ECM connector B-10.
a. Connector B-03 (terminal No. 2) and connector B-10 (terminal No. 55).
b. Connector B-03 (terminal No. 4) and connector B-10 (terminal No. 54).
- Should be less than 2 ohms.
3. Check for the continuity between the oxygen sensor connector B-03 and ground.
a. Connector B-03 (terminal No. 2) and ground.
b. Connector B-03 (terminal No. 4) and ground.
- Not continuity.
Q: Is the harness wire in good condition?
YES : Go to Step 5.
NO : Repair it. Refer to General (Electrical), Harness Connector Inspection. Then go to Step 14.
STEP 5. Check harness connector B-21 at intermediate connector for damage.
Q: Is the harness connector in good condition?
YES : Go to Step 6.
NO : Repair or replace it. Refer to General (Electrical), Harness Connector Inspection. Then go to Step 14.
STEP 6. Measure the right bank injector resistance at intermediate connector B-21.
1. Disconnect the intermediate connector B-21.
2. Measure the resistance between each injector side connector terminal.
a. Measure the resistance between terminal No. 6 and No.7 when measuring No. 1 cylinder.
b. Measure the resistance between terminal No. 6 and No.8 when measuring No. 3 cylinder.
c. Measure the resistance between terminal No. 6 and No.9 when measuring No. 5 cylinder.
- Resistance should be between 10. 5 and 13.5 ohms [at 20 °C (68 °F)].
Q: Is the measured resistance between 10. 5 and 13.5 ohms [at 20 °C (68 °F)]?
YES : Go to Step 9.
NO : Go to Step 7.
STEP 7. Check harness connector B-21 at right bank injector for damage.
1. Remove the intake manifold.
2. Check the right bank injector connector, which deviates from the standard value at Step 6.
Q: Is the harness connector in good condition?
YES : Go to Step 8.
NO : Repair it. Refer to General (Electrical), Harness Connector Inspection. Then go to Step 14.
STEP 8. Check the right bank injector.
1. Check the right bank injector, which deviates from the standard value at Step 6.
2. Measure the resistance between injector side connector terminal No. 1 and No. 2.
Standard value: 10.5 - 13.5 ohms [at 20 °C (68 °F)]
Q: Is the measured resistance between 10.5 and 13.5 ohms [at 20 °C (68 °F)]?
YES : Repair harness wire between the injector intermediate connector and the right bank injector connector because of harness damage. Then go to Step 9.
NO : Replace the injector. Then go to Step 14.
STEP 9. Check for harness between the right bank injector connector B-101, B-103, B-104 and the ECM connector B-10.
1. Disconnect the right bank injector connector B-101, B-103, B-104 and the ECM connector B-10.
2. Measure the resistance between the right bank injector connector B-101, B-103, B-104 and the ECM connector B-10.
a. Connector B-101 (terminal No. 2) and the ECM connector B-10 (terminal No. 2) at No. 1 cylinder injector.
b. Connector B-103 (terminal No. 2) and the ECM connector B-10 (terminal No. 18) at No. 3 cylinder injector.
c. Connector B-104 (terminal No. 2) and the ECM connector B-10 (terminal No. 50) at No. 5 cylinder injector.
- Should be less than 2 ohms.
Q: Is the harness wire in good condition?
YES : Go to Step 10.
NO : Repair it. Refer to General (Electrical), Harness Connector Inspection. Then go to Step 14.
STEP 10. Check the fuel pressure.
Refer to MFI On-vehicle Service-Fuel Pressure Test. Testing and Inspection
Q: Is the fuel pressure normal?
YES : Go to Step 11.
NO : Repair it. Then go to Step 14.
STEP 11. Check for exhaust leaks.
Q: Are there any abnormalities?
YES : Repair it. Then go to Step 14.
NO : Go to Step 12.
STEP 12. Check for intake system vacuum leak.
Q: Are there any abnormalities?
YES : Repair it. Then go to Step 14.
NO : Go to Step 13.
STEP 13. Check the trouble symptoms.
1. Carry out a test drive with the drive cycle pattern. Refer to MFI Diagnostic Function-OBD-II Drive Cycle-Pattern 12. OBD-II Drive Cycle
2. Check the diagnostic trouble code (DTC).
Q: Is DTC P0134 set?
YES : Replace the ECM. When the ECM is replaced,register the ID code. Refer to Diagnosis-ID Codes Registration Judgment Table [Vehicles with KOS] or Diagnosis-ID Codes Registration Judgment Table [Vehicles with WCM]. Then go to Step 14.
NO : It can be assumed that this malfunction is intermittent. Refer to General (Body and Chassis), How to Use Troubleshooting/Inspection Service Points-How to Cope with Intermittent Malfunctions.
STEP 14. Test the OBD-II drive cycle.
1. Carry out a test drive with the drive cycle pattern. Refer to MFI Diagnostic Function-OBD-II Drive Cycle-Pattern 12. OBD-II Drive Cycle
2. Check the diagnostic trouble code (DTC).
Q: Is DTC P0134 set?
YES : Retry the troubleshooting.
NO : The inspection is complete.