On Board Diagnostic (OBD) Drive Cycle

ON BOARD DIAGNOSTIC (OBD) DRIVE CYCLE

Description

The following procedure is designed to execute and complete the OBD monitors and to clear the P1000, I/M readiness code. To complete a specific monitor for repair verification, follow steps 1 through 4, then continue with the step described by the appropriate monitor found under the OBD Monitor Exercised column. For the EVAP/secondary AIR monitor to run, the ambient air temperature must be between 4.4 to 37.8°C (40 to 100°F), and the altitude below 2,438 meters (8,000 feet). If the P1000 code must be cleared in these conditions, the PCM must detect them once (twice on some applications) before the EVAP monitor can be bypassed and DTC P1000 is cleared. The EVAP bypassing procedure is described in the following drive cycle.The OBD drive cycle is carried out using a scan tool. Refer to the manufacturer's instruction manual for each described function.For a detailed description for clearing the DTCs, see Clear the Continuous DTCs and Reset the Emission Monitors Information in the PCM in Engine Control (EC) System.

WARNING:Strict observance of posted speed limits and attention to driving conditions are mandatory when proceeding through the following Drive Cycles.
The IDS or equivalent tester will be used to observe the status of each OBD II monitor at the completion of the OBD II drive cycle. The completion status of the exhaust gas recirculation (EGR), heated oxygen sensor (HO2S), evaporative emission (EVAP), and catalyst efficiency monitors can be monitored during the OBD II drive cycle by viewing the On-Board Readiness Menu on the IDS or equivalent tester.

Drive Cycle Recommendations

1. Most OBD II monitors will complete more readily using a steady foot driving style during cruise or acceleration modes. Operating the throttle in a smooth fashion minimizes the time required for monitor completion.

2. Fuel tank level should be between 1/2 and 3/4 with 3/4 full being the most desirable.

3. The evaporative monitor can operate only during the first 30 minutes of engine operation. When executing the procedure for this monitor, stay in part throttle mode and drive in a smooth fashion to minimize fuel slosh.

For best results, follow each of the following steps as accurately as possible:
4. When bypassing the EVAP engine soak times, the PCM must remain powered (key ON) after clearing the continuous DTCs and relearning emission diagnostic information.