Precautions for ECM Circuit Inspection

When measuring circuit voltage and/or pulse signal at ECM connector, connect the special tool to ECM and ECM connectors while referring to INSPECTION OF ECM AND ITS CIRCUITS  and noting the following.

• ECM connectors are waterproofed. Each terminal of ECM connectors is sealed with grommet. Therefore, do not insert the tester probe into sealed terminal from harness side. When measuring circuit voltage and/or pulse signal at ECM connector, be sure to connect special tool to ECM connectors and insert tester probe into special tool's connectors at harness side. Otherwise, ECM and its circuits may be damaged by water.
• Wire colors of special tool's connectors are different from those of ECM connectors. However, terminal arrangement of these connectors are the same as those of ECM connectors. Therefore, be sure to identify terminal location to measure proper terminal.