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Home >> Mazda >> 2020 >> 3 Base, 4D Hatchback, AWD >> Repair and Diagnosis >> Heating, Ventilation & A/C (HVAC) >> HVAC Control Systems >> Control System - Auto A/C >> Climate Control Unit Inspection (Auto A/C)

Climate Control Unit Inspection (Auto A/C)

  1. Disconnect the negative battery terminal. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION [(US)] .)
  2. Remove the climate control unit with the connector connected. (See CLIMATE CONTROL UNIT REMOVAL/INSTALLATION (AUTO A/C (US)) .)
  3. Connect the negative battery terminal.
  4. Switch the ignition ON (engine off or on).
  5. Connect the negative (-) lead of the tester to body ground.
  6. Insert the positive (+) lead of the tester into each climate control unit terminal and measure the voltage according to the terminal voltage table.
    • If there is any malfunction, inspect the parts under "Inspection item (s)".

    Terminal Voltage Table (Reference) 

G13177474Courtesy of MAZDA MOTORS CORP.
TERMINAL VOLTAGE REFERENCE

Terminal Signal name Connected to Measurement condition Voltage (V) Inspection item (s)
1A B+ F19 10 A fuse Under any condition B+
  • Related wiring harness
  • F19 10 A fuse
1B - - - - -
1C IG F47 15 A fuse Switch the ignition ON (engine off or on) B+
  • Related wiring harness
  • F47 15 A fuse
Switch the ignition off 1.0 or less
1D Glove compartment light Glove compartment light control Light switch at TNS position B+
  • Related wiring harness
Light switch at OFF position 1.0 or less
1E - - - - -
1F - - - - -
1G GND Body ground Under any condition 1.0 or less
  • Related wiring harness
1H - - - - -
1I HS_CAN_H CAN related module Because this terminal is for communication, integrity determination by terminal voltage is not possible.
  • Related wiring harness
1J HS_CAN_H CAN related module Because this terminal is for communication, integrity determination by terminal voltage is not possible.
  • Related wiring harness
1K HS_CAN_L CAN related module Because this terminal is for communication, integrity determination by terminal voltage is not possible.
  • Related wiring harness
1L HS_CAN_L CAN related module Because this terminal is for communication, integrity determination by terminal voltage is not possible.
  • Related wiring harness
1M - - - - -
1N - - - - -
1O - - - - -
1P - - - - -
2A HS_CAN_H CAN related module Because this terminal is for communication, integrity determination by terminal voltage is not possible.
  • Related wiring harness
2B Passenger compartment temperature sensor input Passenger compartment temperature sensor Compared with temperature detected by passenger compartment temperature sensor Refer to graph
  • Related wiring harness
  • Passenger compartment temperature sensor
2C HS_CAN_L CAN related module Because this terminal is for communication, integrity determination by terminal voltage is not possible.
  • Related wiring harness
2D Sensor GND Passenger compartment temperature sensor Under any condition 1.0 or less
  • Related wiring harness
  • Passenger compartment temperature sensor
2E - - - - -
2F - - - - -
2G - - - - -
2H - - - - -
G13177475Courtesy of MAZDA MOTORS CORP.