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Control Module HVAC: Testing and Inspection

EATC Unit Check








Check power supply circuit for EATC unit with ignition switch ON.
1. Disconnect EATC unit harness connector.
2. Connect voltmeter to harness side.
3. Measure voltage between terminals 23, 32 and ground.
If NG, check 7.5A fuse (No.13) and 10 A fuse (No.2) at fuse block.








Check ground circuit for EATC unit with ignition switch OFF.
1. Disconnect EATC unit harness connector.
2. Connect ohmmeter to harness side.
3. Check for continuity between terminal 30 and ground.
If NG, repair harness or connector.

For further trouble diagnosis of the Electronic Automatic Temperature Control System, please see Electronic Automatic Temperature Control / System Diagnosis.