Playback of Stored PIDs

Playback of Stored PIDs

Look for abnormal behavior or values that are clearly incorrect. Inspect signals for abrupt or unexpected changes. For example, during a steady cruise most of the sensor values should be relatively stable. Sensors such as TP, MAF and RPM that change abruptly when the vehicle is traveling at a constant speed are clues to a possible fault area.

NOTE:
Look for agreement in related signals. For example, if TP is changed during acceleration, a corresponding change should occur in IAC, RPM and SPARK DEGREES.

Make sure the signals act in proper sequence. An increase in RPM after the TP is increased is expected. However, if RPM increases without a TP change, then a problem may exist.

1. Select VIEW RECORDER AREAS.

2. Select a viewing area.

3. Select up to four PIDs to review in the table format or two PIDs to review in the graph mode.

PID Table Format:

4. Table Format: Scroll through the PID data while analyzing the information. Look for sudden drops or spikes in the values. (Refer to the TP example or reference the EEC-V Charts and Graphs). Notice the major jump in the TP voltage while scrolling through the information. This example would require a smooth and progressive throttle pedal travel during a key "ON" and engine "OFF" mode.

Analog Sensor Line Graph:

5. Graph Format: Scroll through the PID data while analyzing the information. Look for sudden drops or spikes in the linear lines showing the transformation of values to the line graph. (Refer to the TP example or reference the EEC-V Charts and Graphs). This example would require a smooth and progressive throttle pedal with the key "On" and the engine "Off".