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Clear The Continuous Diagnostic Trouble Codes (DTCs) and Reset The Emission Monitors Information In The Powertrain Control Modu

CLEAR THE CONTINUOUS DIAGNOSTIC TROUBLE CODES (DTCS) AND RESET THE EMISSION MONITORS INFORMATION IN THE POWERTRAIN CONTROL MODULE (PCM)

Description

All on board diagnostic (OBD) scan tools support the clearing of continuous DTCs and resetting of emission monitors information in the PCM.

The clearing of the continuous DTCs allows the scan tool to command the PCM to clear and reset all emission related diagnostic information. On some vehicles, DTC P1000 is stored in the PCM until all the OBD system monitors or components have been tested to satisfy a drive cycle without any other concerns occurring. For more information about a drive cycle, refer to On Board Diagnostic (OBD) Drive Cycle. On Board Diagnostic (OBD) Drive Cycle

The following events occur when the continuous DTCs and the emission monitors information is cleared from the PCM:
- the number of DTCs is reset
- the DTCs are cleared (on vehicles with permanent DTCs, additional vehicle operation is required to complete and pass the appropriate monitors to complete the clearing of permanent DTCs)
- the freeze frame data is cleared
- the diagnostic monitoring test results are reset
- the status of the OBD system monitors is reset