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Rear Climate Control Unit Inspection

  1. Disconnect the negative battery terminal. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION .)
  2. Remove the rear console panel. (See REAR CONSOLE REMOVAL/INSTALLATION .)
  3. Remove the rear climate control unit with the connector connected. (See REAR CLIMATE CONTROL UNIT REMOVAL/INSTALLATION .)
  4. Connect the negative battery terminal. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION .)
  5. Switch the ignition ON (engine off or on).
  6. Connect the negative (-) lead of the tester to body ground.
  7. Insert the positive (+) lead of the tester into each rear climate control unit terminal and measure the voltage according to the terminal voltage table.
    Fig 1: Rear Climate Control Unit Wiring Harness Side Connector Terminals
    G11433692Courtesy of MAZDA MOTORS CORP.
TERMINAL VOLTAGE SPECIFICATION (REFERENCE)

Terminal Signal Name Connected To Measurement Condition Voltage (V) Inspection Item (s)
A Motor operation (VENT) Rear airflow mode actuator Moving towards VENT B+ Rear airflow mode actuator
Moving towards HEAT 1.0 or less
B IG2 Front body control module (FBCM) Switch the ignition ON (engine off or on) B+ Front body control module (FBCM)
Switch the ignition off 1.0 or less
C Motor operation (HEAT) Rear airflow mode actuator Moving towards HEAT B+ Rear airflow mode actuator
Moving towards VENT 1.0 or less
D - - - - -
E Motor operation (COLD) Rear air mix actuator Moving towards HOT 1.0 or less Rear air mix actuator
Moving towards COLD B+
F Blower motor feedback
  • Power MOS FET
  • Rear blower motor
 Fan stopped B+
  • Related wiring harness
  • Power MOS FET
  • Rear blower motor
  • Rear blower relay
  • R. HEATER 40 A fuse
Fan: manual 1st 10.7
Fan: manual 3rd 8.4
Fan: manual 5th 4.4
G Motor operation (HOT) Rear air mix actuator Moving towards HOT B+ Rear air mix actuator
Moving towards COLD 1.0 or less
H Blower fan speed control
  • Power MOS FET
  • Rear blower motor
 Switch the ignition off 1.0 or less
  • Power MOS FET
  • Rear blower motor
Fan stopped (Switch the ignition ON (engine off or on))
Airflow mode: VENT Fan: manual 1st 2.2
Fan: manual 3rd 2.3
Fan: manual 5th 2.5
I - - - - -
J - - - - -
K - - - - -
L - - - - -
M - - - - -
N - - - - -
O Sensor GND
  • Rear air mix actuator
  • Rear airflow mode actuator
 Under any condition 1.0 or less
  • Related wiring harness
  • Rear climate control unit: terminal voltage (W)
P LIN Front climate control unit Because this terminal is for communication, integrity determination by terminal voltage is not possible.
Q Potentiometer input Rear airflow mode actuator VENT 1.0 Rear airflow mode actuator
BI-LEVEL 2.2
HEAT 3.5
R GND Body ground Under any condition 1.0 or less
  • Related wiring harness
S Potentiometer input Rear air mix actuator Set temperature at MAX HOT 3.4 Rear air mix actuator
Set temperature at MAX COLD 1.2
T(1) LIN Rear seat warmer control unit Because this terminal is for communication, integrity determination by terminal voltage is not possible.
U - - - - -
V B+
  • ROOM 25 A fuse
  • INTERIOR 10 A fuse
 Under any condition B+
  • Related wiring harness
  • ROOM 25 A fuse
  • INTERIOR 10 A fuse
W +5V
  • Rear air mix actuator
  • Rear airflow mode actuator
 Under any condition 5
  • Related wiring harness
  • Rear air mix actuator
  • Rear airflow mode actuator
  • Rear climate control unit: terminal voltage (O)
X IG1 C/U IG1 15 A fuse Switch the ignition ON (engine off or on) B+ C/U IG1 15 A fuse
Switch the ignition off 1.0 or less
(1) With Rear seat warmer
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