Readiness Monitor Drive Pattern
READINESS MONITOR DRIVE PATTERNPURPOSE OF READINESS TESTS
- The On-Board Diagnostic (OBD II) system is designed to monitor the performance of emission related components, and indicate any detected abnormalities with DTCs (Diagnostic Trouble Codes). Since various components need to be monitored during different driving conditions, the OBD II system is designed to run separate monitoring programs called Readiness Monitors.
- The hand-held tester's software must be version 9.0 or newer to view the Readiness Monitor status. To view the status, select the following menu items: DIAGNOSIS / ENHANCED OBD II / MONITOR INFO / MONITOR STATUS.
- When the Readiness Monitor status reads COMPL (complete), the necessary conditions have been met for running the performance tests for that Readiness Monitor.
- A generic OBD II scan tool can also be used to view the Readiness Monitor status.
HINT: Many state Inspection and Maintenance (I/M) programs require a vehicle's Readiness Monitor status to show COMPL before beginning emission tests.
The Readiness Monitor will be reset to INCMPL (incomplete) if:
- The ECM has lost battery power or blown a fuse.
- DTCs have been cleared.
- The conditions for running the Readiness Monitor have not been met.
If the Readiness Monitor status shows INCMPL, follow the appropriate Readiness Monitor Drive Pattern to change the status to COMPL.
CAUTION: Strictly observe posted speed limits, traffic laws, and road conditions when performing these drive patterns.
NOTE: These drive patterns represent the fastest method of satisfying all conditions necessary to achieve complete status for each specific Readiness Monitor.
In the event of a drive pattern being interrupted (possibly due to factors such as traffic conditions), the drive pattern can be resumed. In most cases, the Readiness Monitor will still achieve complete status upon completion of the drive pattern.
To ensure completion of the Readiness Monitors, avoid sudden changes in vehicle load and speed (driving up and down hills and/or sudden acceleration).
1. CATALYST MONITOR (Front Heated Oxygen Sensor Type)
a. Preconditions
The monitor will not run unless:
- MIL is OFF.
- Engine Coolant Temperature (ECT) is 75 degrees C (167 degrees F) or higher.
- Intake Air Temperature (IAT) is -10 degrees C (14 degrees F) or higher.
NOTE: The readiness test can be completed in cold ambient conditions (less than -10 degrees C [14 degrees F]), if the drive pattern is repeated a second time after switching the ignition off.
b. Drive Pattern
1. Connect a hand-held tester or OBD II scan tool to the DLC3.
2. Turn the ignition switch to ON
3. Turn the tester or scan tool ON.
4. Clear DTCs (where set).
5. Start the engine, and warm it up until the ECT reaches 75 degrees C (167 degrees F) or higher.
6. Drive the vehicle at between 40 mph and 55 mph (64 km/h and 88 km/h) for approximately 3 minutes.
NOTE: Drive with smooth throttle operation and avoid sudden acceleration.
If the IAT was less than 10 degrees C (50 degrees F) when starting the engine, drive the vehicle at between 40 mph and 55 mph (64 km/h and 88 km/h) for approximately 3 additional minutes.
7. Drive the vehicle at between 35 mph and 45 mph (56 km/h and 72 km/h) for approximately 7 minutes.
NOTE: Drive with smooth throttle operation and avoid sudden deceleration that causes the throttle to close fully.
c. Monitor Status
1. Check the Readiness Monitor status displayed on the tester or scan tool.
2. If the status does not switch to COMPL (complete), make sure that the preconditions have been met, and turn the ignition switch OFF. Then, repeat steps (6) and (7) in Drive Pattern above.
2. EVAP SYSTEM MONITOR (KEY-OFF Type)
a. Preconditions
The monitor will not run unless:
- The fuel tank is less than 90 % full.
- The altitude is less than 8,000 ft (2,450 m).
- The vehicle is at stationary.
- The engine coolant temperature is between 4.4 degrees C and 35 degrees C (40 degrees F to 95 degrees F).
- The intake air temperature is between 4.4 degrees C and 35 degrees C (40 degrees F to 95 degrees F).
b. Monitor Conditions
1. Allow the engine to idle for 300 seconds or more.
2. Turn the ignition switch OFF and wait for 6 hours.
3. Connect the scan tool to the DLC3 to check the monitor status and the preconditions.
4. Check the readiness monitor status.
If the status does not switch to COMPL (complete), restart the engine, make sure that the preconditions have been met, and then perform the Monitor Conditions again.
3. Heated Oxygen (HO2) Sensor Monitors (Front and Rear HO2 Sensor Type)
a. Preconditions
The monitor will not run unless:
- 2 minutes or more have elapsed since the engine was started.
- The Engine Coolant Temperature (ECT) is 75 degrees C (167 degrees F) or more.
- Cumulative driving time at a vehicle speed of 30 mph (48 km/h) or more exceeds 6 minutes.
- Air-fuel ratio feedback control is performed.
- Fuel-cut control is performed for 8 seconds or more (for the Rear HO2 Sensor Monitor)
b. Drive Pattern for Front and Rear HO2 Sensors
1. Connect a hand-held tester or OBD II scan tool to the DLC3.
2. Turn the ignition switch to ON.
3. Turn the tester or scan tool ON.
4. Clear DTCs.
5. Start the engine, and warm it up until the ECT reaches 75 degrees C (167 degrees F) or higher.
6. Drive the vehicle at 30 mph (48 km/h) or more for at least 40 seconds.
7. Allow the engine to idle for 20 seconds or more.
8. Repeat steps (6) and (7) at least 8 times in one driving cycle.
9. Change the transmission to 2nd gear.
10. Accelerate the vehicle to 30 mph (48 km/h) or more by depressing the accelerator pedal for at least 10 seconds.
11. Soon after performing step (10) above, release the accelerator pedal for at least 10 seconds without depressing the brake pedal, in order to execute fuel-cut control.
12. Allow the vehicle to decelerate until the vehicle speed declines to less than 6 mph (10 km/h).
13. Repeat steps from (10) through (12) above at least twice in one driving cycle.
c. Monitor Status
1. Check the Readiness Monitor status displayed on the tester or scan tool.
2. If the status does not switch to COMPL (complete), make sure that the preconditions have been met, and then perform steps from (5) through (13) in Drive Pattern above.
4. Heated Oxygen (HO2) Sensor Heater Monitors (Front and Rear HO2 Sensor Type)
a. Preconditions
The monitor will not run unless:
- The MIL is OFF
b. Drive Pattern
1. Connect a hand-held tester or the OBD II scan tool to the DLC3.
2. Turn the ignition switch to ON.
3. Turn the tester or scan tool ON.
4. Clear the DTC(s) (where set).
5. Start the engine.
6. Allow the engine to idle for 10 minutes or more.
7. Drive the vehicle at 25 mph (40 km/h) or more for at least 2 minutes.
c. Monitor Status
1. Check the Readiness Monitor status displayed on the tester or scan tool.
If the status does not switch to COMPL (complete), restart the engine, make sure the preconditions have been met, and repeat steps (6) and (7) described in the Drive Pattern above.