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HVAC - Diagnostics

Inspection of HVAC Control Module and its Circuit

HVAC control module and its circuits can be checked at HVAC control module wiring coupler by measuring voltage.

CAUTION: HVAC control module can not be checked by itself. It is strictly prohibited to connect voltmeter to HVAC control module with couplers disconnected from it.

Voltage Check




G77-1-G77-6:




G77-6-G77-30:




1. Remove HVAC control module referring to HVAC Control Module Removal and Installation.
2. Check voltage at each terminal as shown given.

NOTE: As each terminal voltage is affected by the battery voltage, confirm that it is 11 V or more when ignition switch is ON.