Scan Tool Testing and Procedures

Typical Scan Tool Values:

If after completing the On-Board Diagnostic (OBD) System Check and finding the TECH 1, diagnostics functioning normally, and no Diagnostic Trouble Codes (DTCs) stored in the Engine Control Modules (ECM's) memory, the "Typical TECH 1 Data Values" may be used for comparison with the values obtained on the Vehicle being tested. The "Typical TECH 1 Data Values" are an average of display values recorded from normally operating Vehicles and are intended to represent what a normally functioning system would display.


NOTE: A Scan Tool that displays faulty data should not be used and the problem should be reported to the manufacturer. The use of a faulty Scan Tool can result in misdiagnosis and unnecessary parts replacement.

Only the parameters listed below are used for diagnosing. If a Scan Tool reads other parameters, those values are not recommended by Isuzu Motors for use in diagnosis.

Conditions:
- Engine at Idle.
- Upper Radiator Hose Hot.
- Closed Throttle.
- Park / Neutral.
- Closed Throttle.
- Accessories OFF".

Normal Condition:
- Diagnostic Trouble Code (DTC) will display.
- The memory cleared by Main Fuse.








I. Disconnect the Sensor or Actuator Wiring Connector (when checking the part component independently).




II. Disconnect the Engine Control Module (ECM) Wiring Connectors.