ECM Terminal Identification

The following conditions must be present before testing pin voltages:

• Engine At Normal Operating Temperature
• Engine Idling In Closed Loop (ENGINE RUN Column)
• ALDL Test Terminal Not Grounded
• Transaxle In Park Or Neutral
• All B+ Voltages Indicate Charging Or Battery Voltage
• All "0" Voltages Are Ground Circuits (Should Read Less Than 0.10 Volt).

Fig 1: ECU Terminal Identification

Courtesy of ISUZU MOTOR CO.