Oxygen Sensor Monitor

OBD System Description - Oxygen Sensor Monitor

System Description / Monitoring Procedure

Primary HO2S
For a primary HO2S, the system monitors maximum and minimum voltage, lean-to-rich and rich-to-lean response rates, and switching cycles. The sensor is also monitored for activity continuously.

Secondary HO2S
A secondary HO2S is used for catalyst monitoring only. During monitoring conditions, the system measures maximum and minimum output voltages and compares the voltage with malfunction criteria.

DTC P0131 / P0132: O2 Sensor Circuit Low / High Voltage (Sensor-1).

Wiring Diagram:

Wiring Diagram

DTC Detecting Condition:

DTC Detecting Condition and Trouble Area

DTC Confirmation Procedure

WARNING:
- When performing a road test, select a place where there is no traffic or possibility of a traffic accident and very careful during testing to avoid occurrence of an accident.
- Road test should be carried out with 2 persons, a driver and tester, on a level road.

NOTE: Check to make sure that the following conditions are satisfied when using this DTC Confirmation Procedure.
- Intake air temp.: -14 °C, 6.8 °F or higher
- Altitude (barometric pressure): 2500 m, 8202 ft or less (560 mmHg, 75 kPa or more)

1. With ignition switch turned OFF, connect scan tool.
2. Turn ON ignition switch and clear DTC using scan tool.
3. Start engine and warm up to normal operating temperature.
4. Drive vehicle at 120 km/h (75 mph) or lower. (engine speed: 1500 - 3000 r/min.)
5. Keep the vehicle speed for 6 min. or more. (Throttle valve opening is kept constant in this step.)
6. Release accelerator pedal and with engine brake applied, keep vehicle coasting (with fuel cut for 10 sec. or more) and then stop vehicle.
7. Check DTC and pending DTC.

Step 1 - 4:

Step 5 - 9:

Step 10 - 11:

DTC Troubleshooting

DTC P0133: O2 Sensor Circuit Slow Response (Sensor-1).

Wiring Diagram:

Wiring Diagram

DTC Detecting Condition:

DTC Detecting Condition and Trouble Area

DTC Confirmation Procedure

WARNING:
- When performing a road test, select a place where there is no traffic or possibility of a traffic accident and very careful during testing to avoid occurrence of an accident.
- Road test should be carried out with 2 persons, a driver and tester, on a level road.

NOTE: Check to make sure that the following conditions are satisfied when using this DTC Confirmation Procedure.
- Intake air temp.: between -14 °C and 70 °C (6.8 °F and 158 °F)
- Altitude (barometric pressure): 2500 m, 8202 ft or less (560 mmHg, 75 kPa or more)

1. Perform step 1 to 6 of DTC P0131 / P0132 confirmation procedure.
2. Check if DTC and pending DTC exists by using scan tool. If not, check if oxygen sensor monitoring test has completed by using scan tool. If not in both of the checks (i.e., no DTC and pending DTC and oxygen sensor monitoring test not completed), check vehicle condition (environmental) and repeat step 3 through 6 of DTC P0131 / P0132 confirmation procedure.

Step 1 - 2:

DTC Troubleshooting

DTC P0134: O2 Sensor No Activity Detected (Sensor-1).

Wiring Diagram:

Wiring Diagram

DTC Detecting Condition:

DTC Detecting Condition and Trouble Area

DTC Confirmation Procedure

WARNING:
- When performing a road test, select a place where there is no traffic or possibility of a traffic accident and very careful during testing to avoid occurrence of an accident.
- Road test should be carried out with 2 persons, a driver and tester, on a level road.

NOTE: Check to make sure that the following conditions are satisfied when using this DTC Confirmation Procedure.
- Intake air temp.: between -14 °C and 70 °C (6.8 °F and 158 °F)
- Altitude (barometric pressure): 2500 m, 8202 ft or less (560 mmHg, 75 kPa or more)

1. Perform step 1 to 6 of DTC P0131 / P0132 confirmation procedure.
2. Check if DTC and pending DTC exists by using scan tool. If not, check if oxygen sensor monitoring test has completed by using scan tool. If not in both of the checks (i.e., no DTC and pending DTC and oxygen sensor monitoring test not completed), check vehicle condition (environmental) and repeat step 3 through 6 of DTC P0131 / P0132 confirmation procedure.

Step 1 - 4:

Step 5 - 10:

DTC Troubleshooting

DTC P0137 / P0138: O2 Sensor Circuit Low / High Voltage (Sensor-2).

Wiring Diagram:

Wiring Diagram

DTC Detecting Condition:

DTC Detecting Condition and Trouble Area

DTC Confirmation Procedure

WARNING:
- When performing a road test, select a place where there is no traffic or possibility of a traffic accident and very careful during testing to avoid occurrence of an accident.
- Road test should be carried out with 2 persons, a driver and tester, on a level road.

NOTE: Check to make sure that the following conditions are satisfied when using this DTC Confirmation Procedure.
- Intake air temp.: -14 °C, 6.8 °F or higher
- Altitude (barometric pressure): 2500 m, 8202 ft or less (560 mmHg, 75 kPa or more)

1. With ignition switch turned OFF, connect scan tool.
2. Turn ON ignition switch and clear DTC using scan tool.
3. Start engine and warm up to normal operating temperature.
4. Increase vehicle speed to 40 mph (60 km/h) or more. (engine speed: 2500 - 3000 r/min.)
5. Keep the vehicle speed for 10 min. or more. (Throttle valve opening is kept constant in this step.)
6. Release accelerator pedal and with engine brake applied, keep vehicle coasting (with fuel cut for 4 sec. or more), then stop vehicle and run engine at idle speed for 6 sec or more.
7. Check DTC and pending DTC.