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HVAC Control Module and Its Circuits Inspection

HVAC Control Module and Its Circuits Inspection

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.


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

Voltage Check
1. Remove HVAC control module. Refer to HVAC Control Module Removal and Installation.
2. Connect HVAC control module and body control module couplers to HVAC control module and body control module.
3. Check each terminal voltage with couplers connected by referring to HVAC Control Module Voltage Table.

Terminal arrangement of HVAC control module (viewed from harness side):




HVAC Control Module Voltage Table (Part 1):




HVAC Control Module Voltage Table (Part 2):






Reference waveform No. 1
Serial communication line to BCM (1)

Reference waveform No. 1: