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Checking Monitor Status

The purpose of the monitor result (mode 06) is to allow access to the results for on-board diagnostic monitoring tests of specific components/systems that are not continuously monitored. Examples are catalyst, evaporative emission (EVAP) and thermostat.

The monitor result allows the OBD II scan tool to display the monitor status, test value, minimum test limit and maximum test limit. These data are displayed after the vehicle has been driven to run the monitor.

When the test value is not between the minimum test limit and maximum test limit, the ECM (PCM) interprets this as a malfunction. When the component is not malfunctioning, if the difference of the test value and test limit is very small, the component will malfunction in the near future. Perform the following instruction to view the monitor status. Although this instruction refers to the Lexus/Toyota diagnostic tester, it can be checked using a generic OBD II scan tool. Refer to your scan tool operator's manual for specific procedures.

  1. PERFORM MONITOR DRIVE PATTERN 
    1. Connect the Techstream to the DLC3.
    2. Turn the ignition switch ON and turn the tester ON.
    3. Clear the DTCs (see DTC CHECK / CLEAR ).
    4. Run the vehicle in accordance with the applicable drive pattern described in READINESS MONITOR DRIVE PATTERN (see READINESS MONITOR DRIVE PATTERN ). Do not turn the ignition switch OFF.
      NOTE: The test results will be lost if the ignition switch is turned OFF.
  2. ACCESS MONITOR RESULT 
    1. Select from the Techstream menus: Powertrain / Engine and ECT / Monitor / Result. The monitor status appears after the component name.
      • Pass: The component is functioning normally.
      • Fail: The component is malfunctioning.
    2. Confirm that the component is either Pass or Fail.
    3. Select the component and press ENTER. The accuracy test value appears if the monitor status is either Pass or Fail.
  3. CHECK COMPONENT STATUS 
    1. Compare the test value with the minimum test limit (MIN LIMIT) and maximum test limit (MAX LIMIT).
    2. If the test value is between the minimum test limit and maximum test limit, the component is functioning normally. If not, the component is malfunctioning. The test value is usually significantly higher or lower than the test limits. If the test value is on the borderline of the test limits, the component will malfunction in the near future.

      HINT:

      The monitor result might on rare occasions be Pass even if the malfunction indicator lamp (MIL) is illuminated. This indicates the system malfunctioned on a previous driving cycle. This might be caused by an intermittent problem.

  4. MONITOR RESULT INFORMATION 

    If you use a generic scan tool, multiply the test value by the scaling value listed below.

    1. Front Heated Oxygen Sensor

      Bank 1 Sensor 1 

      FRONT HEATED OXYGEN SENSOR SPECIFICATIONS

      Monitor ID Test ID Scaling Unit Description of Test Value
      $01 $03 Multiply by 0.001 V Criteria of Lean sensor O2S is Lean when voltage is lower than this value
      $01 $04 Multiply by 0.001 V Criteria of Rich sensor O2S is Rich when voltage is higher than this value
      $01 $05 Multiply by 0.001 Seconds Rich - Lean switch time
      $01 $06 Multiply by 0.001 Seconds Lean - Rich switch time
      $01 $07 Multiply by 0.001 V Minimum sensor voltage
      $01 $08 Multiply by 0.001 V Maximum sensor voltage
      $01 $81 Multiply by 0.001 Seconds Duration while sensor voltage stuck Lean or Rich
      $01 $82 Multiply by 0.001 Seconds Time of one cycle of sensor output

      Bank 2 Sensor 1 

      FRONT HEATED OXYGEN SENSOR SPECIFICATIONS

      MID TID Scaling Unit Description
      $05 $03 Multiply by 0.001 V Criteria of Lean sensor O2S is Lean when voltage is lower than this value
      $05 $04 Multiply by 0.001 V Criteria of Rich sensor O2S is Rich when voltage is higher than this value
      $05 $05 Multiply by 0.001 Seconds Rich - Lean switch time
      $05 $06 Multiply by 0.001 Seconds Lean - Rich switch time
      $05 $07 Multiply by 0.001 V Minimum sensor voltage
      $05 $08 Multiply by 0.001 V Maximum sensor voltage
      $05 $81 Multiply by 0.001 Seconds Duration while sensor voltage stuck Lean or Rich
      $05 $82 Multiply by 0.001 Seconds Time of one cycle of sensor output
    2. Rear Heated Oxygen Sensor

      Bank 1 Sensor 2 

      REAR HEATED OXYGEN SENSOR SPECIFICATIONS

      MID TID Scaling Unit Description
      $02 $05 Multiply by 0.001 Seconds Rich - Lean switch time
      $02 $06 Multiply by 0.001 Seconds Lean - Rich switch time
      $02 $07 Multiply by 0.001 V Minimum sensor voltage
      $02 $08 Multiply by 0.001 V Maximum sensor voltage
      $02 $84 Multiply by 0.01526 % Percentage of time that sensor voltage is lower than 0.05 V
      $02 $85 Multiply by 0.01526 % Percentage of time that sensor voltage is higher than 0.7 V
      $02 $86 Multiply by 0.1 Seconds Duration that sensor voltage is higher than 0.45 V
      $02 $87 Multiply by 0.01526 % Percentage of time that sensor voltage is higher than 0.45 V
      $02 $88 Multiply by 0.1 Seconds Cumulative time that sub-feedback compensation factor remained 7% or more
      $02 $89 Multiply by 0.01526 % Percentage of time that sub-feedback compensation factor remained 0.05 V or more
      $02 $8A Multiply by 1 Time Frequency of sensor switching
      $02 $8B Multiply by 0.001 Seconds 0.35 - 0.2 V sensor switch time
      $02 $8D Multiply by 0.001 Seconds Duration that sensor voltage drops to 0.2 V during fuel cut
      $02 $8F Multiply by 0.0003 Grams Maximum oxygen storage capacity

      Bank 2 Sensor 2 

      REAR HEATED OXYGEN SENSOR SPECIFICATIONS

      MID TID Scaling Unit Description
      $06 $05 Multiply by 0.001 Seconds Rich - Lean switch time
      $06 $06 Multiply by 0.001 Seconds Lean - Rich switch time
      $06 $07 Multiply by 0.001 V Minimum sensor voltage
      $06 $08 Multiply by 0.001 V Maximum sensor voltage
      $06 $84 Multiply by 0.01526 % Percentage of time that sensor voltage is lower than 0.05 V
      $06 $85 Multiply by 0.01526 % Percentage of time that sensor voltage is higher than 0.7 V
      $06 $86 Multiply by 0.1 Seconds Duration that sensor voltage is higher than 0.45 V
      $06 $87 Multiply by 0.01526 % Percentage of time that sensor voltage is higher than 0.45 V
      $06 $88 Multiply by 0.1 Seconds Cumulative time that sub-feedback compensation factor remained 7% or more
      $06 $89 Multiply by 0.01526 % Percentage of time that sub-feedback compensation factor remained 0.05 V or more
      $06 $8A Multiply by 1 Time Frequency of sensor switching
      $06 $8B Multiply by 0.001 Seconds 0.35 - 0.2 V sensor switch time
      $06 $8D Multiply by 0.001 Seconds Duration that sensor voltage drops to 0.2 V during fuel cut
      $06 $8F Multiply by 0.0003 Grams Maximum oxygen storage capacity
    3. Catalyst - Front O2S and Rear O2S Type

      Bank 1 

      CATALYST - FRONT O2S AND REAR O2S TYPE SPECIFICATIONS

      MID TID Scaling Unit Description
      $21 $A1 Multiply by 0.0003 No dimension Locus length ratio of O2S sensor 1 and sensor 2
      $21 $A2 Multiply by 0.0003 No dimension Voltage area ratio of O2S sensor 1 and sensor 2
      $21 $A3 Multiply by 0.0003 No dimension Locus length ratio of O2S sensor 1 and sensor 2
      $21 $A4 Multiply by 0.0003 No dimension O2S frequency ratio of sensor 2 and sensor 1
      $21 $A5 Multiply by 0.0003 No dimension Locus length ratio of O2S sensor 1 and sensor 2
      $21 $A6 Multiply by 0.0003 No dimension Voltage area ratio of O2S sensor 1 and sensor 2

      Bank 2 

      CATALYST - FRONT O2S AND REAR O2S TYPE SPECIFICATIONS

      MID TID Scaling Unit Description
      $22 $A1 Multiply by 0.0003 No dimension Locus length ratio of O2S sensor 1 and sensor 2
      $22 $A2 Multiply by 0.0003 No dimension Voltage area ratio of O2S sensor 1 and sensor 2
      $22 $A3 Multiply by 0.0003 No dimension Locus length ratio of O2S sensor 1 and sensor 2
      $22 $A4 Multiply by 0.0003 No dimension O2S frequency ratio of sensor 2 and sensor 1
      $22 $A5 Multiply by 0.0003 No dimension Locus length ratio of O2S sensor 1 and sensor 2
      $22 $A6 Multiply by 0.0003 No dimension Voltage area ratio of O2S sensor 1 and sensor 2
    4. EVAP-Key-off Type

      EVAP 

      EVAP-KEY-OFF TYPE SPECIFICATIONS

      Monitor ID Test ID Scaling Unit Description
      $3D $C9 Multiply by 0.001 kPa Test value for small leak (P0456)
      $3D $CA Multiply by 0.001 kPa Test value for gross leak (P0455)
      $3D $CB Multiply by 0.001 kPa Test value for leak detection pump stuck OFF (P2401)
      $3D $CD Multiply by 0.001 kPa Test value for leak detection pump stuck ON (P2402)
      $3D $CE Multiply by 0.001 kPa Test value for vent valve stuck OFF (P2420)
      $3D $CF Multiply by 0.001 kPa Test value for vent valve stuck ON (P2419)
      $3D $D0 Multiply by 0.001 kPa Test value for reference orifice low flow (P043E)
      $3D $D1 Multiply by 0.001 kPa Test value for reference orifice high flow (P043F)
      $3D $D4 Multiply by 0.001 kPa Test value for purge VSV stuck closed (P0441)
      $3D $D5 Multiply by 0.001 kPa Test value for purge VSV stuck open (P0441)
      $3D $D7 Multiply by 0.001 kPa Test value for purge flow insufficient (P0441)
    5. Misfire

      Misfire 

      MISFIRE CHART

      Monitor ID Test ID Scaling Unit Description
      $A1 $0B Multiply by 1 Time Total EWMA misfire count of all cylinders in last ten driving cycles
      EWMA: Exponential Weighted Moving Average
      $A1 $0C Multiply by 1 Time
      • When ignition switch is ON, total misfire count of all cylinders in last driving cycle is displayed.
      • While engine is running, total misfire count of all cylinders in current driving cycle is displayed.
      $A2 SOB Multiply by 1 Time Total EWMA misfire count of cylinder 1 in last ten driving cycles
      $A2 $0C Multiply by 1 Time
      • When ignition switch is ON, total misfire count of cylinder 1 in last driving cycle is displayed.
      • While engine is running, total misfire count of cylinder 1 in current driving cycle is displayed.
      $A3 SOB Multiply by 1 Time Total EWMA misfire count of cylinder 2 in last ten driving cycles
      $A3 $0C Multiply by 1 Time
      • When ignition switch is ON, total misfire count of cylinder 2 in last driving cycle is displayed.
      • While engine is running, total misfire count of cylinder 2 in current driving cycle is displayed.
      $A4 SOB Multiply by 1 Time Total EWMA misfire count of cylinder 3 in last ten driving cycles
      $A4 $0C Multiply by 1 Time
      • When ignition switch is ON, total misfire count of cylinder 3 in last driving cycle is displayed.
      • While engine is running, total misfire count of cylinder 3 in current driving cycle is displayed.
      $A5 $0B Multiply by 1 Time Total EWMA misfire count of cylinder 4 in last ten driving cycles
      $A5 $0C Multiply by 1 Time
      • When ignition switch is ON, total misfire count of cylinder 4 in last driving cycle is displayed.
      • While engine is running, total misfire count of cylinder 4 in current driving cycle is displayed.
      $A6 SOB Multiply by 1 Time Total EWMA misfire count of cylinder 5 in last ten driving cycles
      $A6 $0C Multiply by 1 Time
      • When ignition switch is ON, total misfire count of cylinder 5 in last driving cycle is displayed.
      • While engine is running, total misfire count of cylinder 5 in current driving cycle is displayed.
      $A7 SOB Multiply by 1 Time Total EWMA misfire count of cylinder 6 in last ten driving cycles
      $A7 $0C Multiply by 1 Time
      • When ignition switch is ON, total misfire count of cylinder 6 in last driving cycle is displayed.
      • While engine is running, total misfire count of cylinder 6 in current driving cycle is displayed.
      $A8 SOB Multiply by 1 Time Total EWMA misfire count of cylinder 7 in last ten driving cycles
      $A8 $0C Multiply by 1 Time
      • When ignition switch is ON, total misfire count of cylinder 7 in last driving cycle is displayed.
      • While engine is running, total misfire count of cylinder 7 in current driving cycle is displayed.
      $A9 SOB Multiply by 1 Time Total EWMA misfire count of cylinder 8 in last ten driving cycles
      $A9 $0C Multiply by 1 Time
      • When ignition switch is ON, total misfire count of cylinder 8 in last driving cycle is displayed.
      • While engine is running, total misfire count of cylinder 8 in current driving cycle is displayed.