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Readiness Monitor Drive Pattern

PURPOSE OF READINESS TESTS 

CAUTION: Strictly observe posted speed limits, traffic laws, and road conditions when performing these drive patterns.
NOTE: The following drive patterns are the fastest method of completing all the requirements necessary for making the readiness monitor status read "complete".
If forced to momentarily stop a drive pattern due to traffic or other factors, the drive pattern can be resumed. Upon completion of the drive pattern, in most cases, the readiness monitor status will change to "complete".
Sudden changes in vehicle load and speed, such as driving up and down hills and/or sudden acceleration, hinder readiness monitor completion.

Contents: 

CONTENTS TABLE

TITLE STEP(s)
Catalyst Monitor 1
EVAP System Monitor 2
HO2S (heated oxygen sensor) Monitor 3
HO2S (heated oxygen sensor) Heater Monitor 4
  1. CATALYST MONITOR 
    Fig 1: Identifying Catalyst Monitor Pattern
    G03003870Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Preconditions

      The monitor will not run unless:

      • The MIL is OFF.
      • ECT is 75°C (167°F) or greater.
      • IAT is -10°C (14°F) or greater.
      NOTE: The readiness test can be completed in cold ambient conditions (less than -10°C/14°F). Finish the drive pattern, turn the ignition switch OFF and then on again, and repeat the drive pattern a second time.
    2. Drive Pattern
      1. Connect the hand-held tester to DLC3 to check readiness monitor status and preconditions (refer to step "a").
      2. Drive vehicle at 64 to 88 km/h (40 to 55 mph) for approximately 3 minutes.
        NOTE: Drive with smooth throttle operation and avoid sudden acceleration.
        If IAT was less than 10°C (50°F) when the engine was started, drive the vehicle at 64 to 88 km/h (40 to 55 mph) for an additional 3 minutes.
      3. Drive the vehicle at 56 to 72 km/h (35 to 45 mph) for approximately 7 minutes.
        NOTE: Drive with smooth throttle operation and avoid sudden closure of the throttle.
      4. Check the status of the readiness monitor on the hand-held tester display. If readiness monitor status did not switch to complete, ensure preconditions are met, turn the ignition OFF, and then repeat steps (2) and (3).
  2. EVAP SYSTEM MONITOR 
    NOTE: A cold soak must be performed prior to conducting the drive pattern to complete the Internal Pressure readiness monitor.
    1. Cold Soak Preconditions

      The monitor will not run unless:

      • The MIL is OFF.
      • Fuel level is approximately 1/2 to 3/4 full.
      • Altitude is 2,400 m (7,874 feet) or less.
    2. Cold Soak Procedure

      Let vehicle cold soak for 8 hours or until the difference between IAT and ECT is less than 7°C (13°F).

      Fig 2: Identifying EVAP System Monitor Pattern
      G03003871Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Preconditions

      The monitor will not run unless:

      • The MIL is OFF.
      • Fuel level is approximately 1/2 to 3/4 full.
      • The altitude is 2,400 m (7,874 feet) or less.
      • ECT is between 4.4°C and 35°C (40°F and 95°F).
      • IAT is between 4.4°C and 35°C (40°F and 95°F).
      • The cold soak procedure has been completed.
      • Before starting the engine, the difference between ECT and IAT must be less than 7°C (13°F).

      HINT:

      • Example 1:

        ECT = 24°C (75°F)

        IAT = 16°C (60°F)

        Difference between ECT and IAT is 8°C (15°F).

        --> The monitor will not run because difference between ECT and IAT is greater than 7°C (13°F).

      • Example 2:

        ECT = 21°C (70°F)

        IAT = 20°C (68°F)

        Difference between ECT and IAT is 1°C (2°F).

        --> The monitor will run because "IAT - ECT" is between -7 and 11.1°C (-12.6 and 20°F)

      NOTE: The readiness test can be completed in cold ambient conditions (less than 4.4°C (40°F)) and/or high altitudes (more than 2,400 m (8,000 feet)). Finish the drive pattern, turn the ignition switch OFF and then on again, and repeat the drive pattern a second time.
    4. Drive Pattern
      1. Connect the hand-held tester to DLC3 to check monitor status and preconditions (refer to step  a).
      2. Release pressure in fuel tank by removing the fuel tank cap and then reinstalling it.
      3. Start the engine and allow it to idle until ECT is 75°C (167°F) or more.
      4. Run the engine at 3,000 RPM for about 10 seconds.
      5. With the engine idling, turn the A/C ON to create a slight electrical load. Wait 15 to 50 minutes.
      NOTE: If the vehicle does not have A/C, put a slight electrical load on the engine by following the steps below:
      • Set the parking brake securely.
      • Use wheel chocks to secure the tires.
      • Move the shift lever to drive (position: D) and allow engine to idle for 15 to 50 minutes. Check if the readiness monitor status.
  3. HEATED OXYGEN SENSOR MONITOR 
    Fig 3: Identifying Heated Oxygen Sensor Monitor Pattern
    G03003872Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Preconditions

      The monitor will not run unless:

      The MIL is OFF.

    2. Drive Pattern
      1. Connect the hand-held tester to the DLC3 to check monitor status and preconditions.
      2. Start the engine and allow it to idle for 2 minutes or more.
      3. Drive the vehicle at 40 km/h (25 mph) or more at least 50 seconds.
      4. Stop the vehicle and allow the engine to idle for 40 seconds or more.
      5. Perform steps (3) and (4) ten times.
      6. If readiness status dose not switch to complete, ensure preconditions are met, turn ignition off and then repeat steps (1) through (5).
  4. HEATED OXYGEN SENSOR HEATER MONITOR 
    Fig 4: Identifying Heated Oxygen Sensor Heater Monitor Pattern
    G03003873Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Preconditions

      The monitor will not run unless:

      The MIL is OFF.

    2. Drive Pattern
      1. Connect the hand-held tester to DLC3 to check monitor status and preconditions (refer to step "a").
      2. Start the engine and allow it to idle for 8 minutes and 20 seconds or more.
      3. Drive the vehicle at 40 km/h (25 mph) or more for at least 2 minutes.
      4. Check the readiness monitor status. If the readiness monitor status did not change to "complete", double-check the preconditions, turn the ignition switch OFF, and repeat steps (2) to (3).