CLIMATE CONTROL UNIT INSPECTION [FULL-AUTO AIR CONDITIONER]
2016 – MX-5 – HVAC
CLIMATE CONTROL UNIT INSPECTION [FULL-AUTO AIR CONDITIONER]
1. Disconnect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION.)
2. Remove the following parts:
a. Selector lever knob (AT) (See AUTOMATIC TRANSMISSION SHIFT MECHANISM REMOVAL/INSTALLATION.)
b. Shift lever knob (MT)
c. Shift panel component (See SHIFT PANEL REMOVAL/INSTALLATION.)
d. Upper panel (See UPPER PANEL REMOVAL/INSTALLATION.)
e. Parking brake lever boot panel (See PARKING BRAKE LEVER BOOT PANEL REMOVAL/INSTALLATION.)
f. Rear console (See REAR CONSOLE REMOVAL/INSTALLATION.)
g. Front console panel (See FRONT CONSOLE PANEL REMOVAL/INSTALLATION.)
h. Front console component (See FRONT CONSOLE REMOVAL/INSTALLATION.)
i. Scuff plate (See SCUFF PLATE REMOVAL/INSTALLATION.)
j. Front side trim (See FRONT SIDE TRIM REMOVAL/INSTALLATION.)
k. A-pillar trim (See A-PILLAR TRIM REMOVAL/INSTALLATION.)
l. Hood release lever (See HOOD RELEASE LEVER AND RELEASE CABLE REMOVAL/INSTALLATION.)
m. Driver-side lower panel (See DRIVER-SIDE LOWER PANEL REMOVAL/INSTALLATION.)
n. Passenger-side lower panel (See PASSENGER-SIDE LOWER PANEL REMOVAL/INSTALLATION.)
o. Center panel No.1 (See CENTER PANEL No.1 REMOVAL/INSTALLATION.)
3. Remove the climate control unit with the connector connected. (See CLIMATE CONTROL UNIT REMOVAL/INSTALLATION [FULL-AUTO AIR CONDITIONER].)
4. Connect the negative battery cable. (See NEGATIVE BATTERY CABLE 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 climate control unit terminal and measure the voltage according to the terminal voltage table.
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If there is any malfunction, inspect the parts under “Inspection item (s)”.
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If the parts under “Inspection item (s)” are found to be normal (except for terminal Q), replace the climate control unit. (See CLIMATE CONTROL UNIT REMOVAL/INSTALLATION [FULL-AUTO AIR CONDITIONER].)
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For terminal Q, first try replacing the blower fan controller. If there is still any malfunction, replace the climate control unit. (See CLIMATE CONTROL UNIT REMOVAL/INSTALLATION [FULL-AUTO AIR CONDITIONER].)
Terminal voltage table (reference)
|
Terminal |
Signal name |
Connected to |
Measurement condition |
Voltage (V) |
Inspection item (s) |
|
|
A |
— |
— |
— |
— |
— |
|
|
B |
MS_CAN_L |
CAN related module |
Because this terminal is for communication, integrity determination by terminal voltage is not possible. |
|
||
|
C |
GND |
Body ground |
Under any condition |
1.0 or less |
|
|
|
D |
MS_CAN_H |
CAN related module |
Because this terminal is for communication, integrity determination by terminal voltage is not possible. |
|
||
|
E |
Sensor GND |
|
Under any condition |
1.0 or less |
|
|
|
F |
Passenger compartment temperature sensor input |
Passenger compartment temperature sensor |
Compared with temperature detected by passenger compartment temperature sensor |
Refer to graph 1 |
|
|
|
G |
Potentiometer input |
Air mix actuator |
Set temperature at HOT |
2.9 or more |
|
|
|
Set temperature at COLD |
1.0 or less |
|||||
|
H |
+5V |
|
Under any condition |
5 |
|
|
|
I |
Potentiometer input |
Airflow mode actuator |
VENT |
0.5 or less |
|
|
|
BI-LEVEL |
1.45 |
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|
HEAT |
2.44 |
|||||
|
HEAT/DEF |
3.44 |
|||||
|
DEFROSTER |
4.41 or more |
|||||
|
J |
Evaporator temperature sensor input |
Evaporator temperature sensor |
Compared with temperature detected by evaporator temperature sensor |
Refer to graph 2 |
|
|
|
K |
Solar radiation sensor input |
Solar radiation sensor |
Sunlight shined directly on solar radiation sensor |
Voltage value is output |
|
|
|
Blocking light to solar radiation sensor |
0 |
|||||
|
L |
B+ |
|
Under any condition |
B+ |
|
|
|
M |
— |
— |
— |
— |
— |
|
|
N |
IG1 |
Ignition relay |
Switch the ignition ON (engine off or on) |
B+ |
|
|
|
Switch the ignition off |
1.0 or less |
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|
O |
— |
— |
— |
— |
— |
|
|
P |
— |
— |
— |
— |
— |
|
|
Q |
Blower fan speed control |
Blower fan controller |
Switch the ignition off |
1.0 or less |
|
|
|
Fan stopped (Switch the ignition ON (engine off or on)) |
B+ |
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|
Fan: manual 1st |
11.03 |
||||
|
Fan: manual 3rd |
7.68 |
|||||
|
Fan: manual 7th |
5.68 |
|||||
|
R |
— |
— |
— |
— |
— |
|
|
S |
Motor operation (RECIRCULATE) |
Air intake actuator |
Moving towards RECIRCULATE |
B+ |
|
|
|
Moving towards FRESH |
1.0 or less |
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|
T |
Motor operation (VENT) |
Airflow mode actuator |
Moving towards VENT |
B+ |
|
|
|
Moving towards DEFROSTER |
1.0 or less |
|||||
|
U |
Motor operation (FRESH) |
Air intake actuator |
Moving towards RECIRCULATE |
1.0 or less |
|
|
|
Moving towards FRESH |
B+ |
|||||
|
V |
Motor operation (DEFROSTER) |
Airflow mode actuator |
Moving towards DEFROSTER |
B+ |
|
|
|
Moving towards VENT |
1.0 or less |
|||||
|
W |
Motor operation (COLD) |
Air mix actuator |
Moving towards HOT |
1.0 or less |
|
|
|
Moving towards COLD |
B+ |
|||||
|
X |
Motor operation (HOT) |
Air mix actuator |
Moving towards HOT |
B+ |
|
|
|
Moving towards COLD |
1.0 or less |
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|
|
|
