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Accumulating PCM Data







ACCUMULATING PCM DATA

Accumulating PCM data can be done in a number of ways. Gather as much data as possible when the malfunction is occurring to prevent misdiagnosis. Data should be accumulated in different operating conditions and based on the customer description of the intermittent fault. Acquisition of PCM PID data using a scan tool is one of the easiest ways to gather information.

For information on the functions of your scan tool, refer to the manufacturer manual for scan tool instructions.

Below is a list of the functions available:
- Selecting and viewing PIDs
- Storing PIDs
- Recording measurements along with PIDs
- Playback of stored PIDs
- Peripheral inputs

Comparing PCM Data
After the PCM values have been acquired, it is necessary to determine the fault area. Typically, it will require the comparison of the actual values from the vehicle to the typical values from Reference Value Charts in Reference Values. Normal Scan Data Values - Includes PIDs