Heated Oxygen Sensor Monitor

This monitor applies to DTCs P0132, P0133, P0137, P0138, P0139, P0152, P0153, P0158 and P0159. Following conditions must be met during the test:

• Engine coolant temperature must be 176°F (80°C) or more.
• Atmospheric temperature is 14°F (-10°C) or more.
• Selector lever is in "D" range.

Monitor takes about 5 minutes to complete. To run monitor, use illustration. See . Perform steps as follows:

1. Remove all test equipment from vehicle and install all components and connectors that were removed or disconnected during testing.
2. After engine is completely warmed up, turn ignition off.
3. Start engine and quickly accelerate to 35-40 MPH.
4. While keeping accelerator pedal position constant, keep speed at 35-40 MPH for 120 seconds or more.
5. Return vehicle to shop and turn ignition off. Confirm that DTC is not set. If DTCs P0132, P0133, P0137, P0138, P0139, P0152, P0153, P0158 or P0159 is set, refer to specific HO2S Circuit Malfunction procedure in DIAGNOSTIC TESTS. See DIAGNOSTIC TROUBLE CODE DEFINITIONS  for directions.

Fig 1: Running Heated Oxygen Sensor Monitor

Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.