HVAC Control Module and its Circuits Inspection
HVAC Control Module and its Circuits InspectionCAUTION:
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.
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)
Ter. G52-6 - G52-19:
Ter. G52-20 - G52-30:
HVAC Control Module Voltage Table
Reference Waveform
NOTE: The shape of waveform varies with engine coolant temperature.
Waveform at 0 degrees C (32 degrees F)
Waveform at 40 degrees C (104 degrees F)
Waveform at 80 degrees C (176 degrees F)
Reference Graph