PCM Data Description
PCM Data DescriptionThe following information will assist in diagnosing emission or driveability problems. The displays can be viewed while the vehicle is being driven. Refer to the On Board Diagnostic (OBD) System Check for additional information.
The data messages displayed on the scan tool are divided into Engine, Specific Engine and DTC lists as follows:
Engine Data
- Engine 1 - Contains general information regarding fuel delivery, Ignition Control (IC), Knock Sensor (KS), Evaporative Emissions (EVAP) and engine operating conditions.
- Engine 2 - Contains general information regarding fuel delivery Output Controls, Ignition Control (IC), and Air Conditioning (A/C) and basic engine operating conditions.
Specific Engine Data
- Misfire - Contains information specific to the diagnosis of misfire and data required to verify proper operation with regard to misfire.
- O2S - Contains information specific to the Oxygen Sensor (O2S 1) and Rear Heated Oxygen Sensor (HO2S 2) diagnosis and data required to verify proper operation of the sensors.
- EGR- Contains the information specific to the Exhaust Gas Recirculation System (EGR) and the Evaporative Emissions System (EVAP) required for diagnosis.
DTC Data
- Freeze Frame - Contains information collected at the time a type A or type B DTC Malfunction Indicator Lamp (MIL) was illuminated. This allows the technician to re-create conditions when a MIL occurred and to verify proper operation within these conditions.
- Failure Records - Contains the information at the time a diagnostic test failed. The failure records data is not necessarily associated with the MIL.