Control System (HVAC): Diagnosis Mazda 3 BL

AIR MIX ACTUATOR INSPECTION

Scheme 45

Scheme 46

1. Connect battery positive voltage to air mix actuator terminal D (or F), connect terminal F (or D) to ground, and then verify that the air mix actuator operates as shown in the table. If the operation condition is not normal, replace the air mix actuator. AIR MIX ACTUATOR TERMINALS REFERENCE Terminal Air mix actuator operation D F B+ Ground HOT --> COLD Ground B+ COLD --> HOT
2. Verify that the resistance between terminals B and C, C and A matches the air mix actuator operation as shown in the graph. If the operation condition and resistance are not normal, replace the air mix actuator.

Scheme 47

1. Disconnect the negative battery cable.
2. Remove the airflow mode rod from the airflow mode actuator.
3. Remove in the order indicated in the table.
4. Install in the reverse order of removal.

AIRFLOW MODE ACTUATOR INSPECTION

Scheme 48

Scheme 49

1. Connect battery positive voltage to airflow mode actuator terminal D (or F), connect terminal F (or D) to ground, and then verify that the airflow mode actuator operates as shown in the table. If the operation condition is not normal, replace the airflow mode actuator. AIRFLOW MODE ACTUATOR TERMINALS REFERENCE Terminal Airflow mode actuator operation D F B+ Ground VENT --> DEFROSTER Ground B+ DEFROSTER --> VENT
2. Verify that the resistance between terminals A and C, C and B matches the airflow mode actuator operation as shown in the graph. If the operation condition and resistance are not normal, replace the airflow mode actuator.

BLOWER MOTOR INSPECTION

Connect battery positive voltage to blower motor terminal A, connect terminal B to ground, and then verify its operation.

Scheme 50

1. If there is any malfunction, replace the blower motor.

Scheme 51

1. Disconnect the negative battery cable.
2. Remove the PJB and PJB bracket. (See «PASSENGER JUNCTION BOX (PJB) REMOVAL/INSTALLATION»(ref-345241-S29864541242009102000000) .)
3. Remove in the order indicated in the table.
4. Install in the reverse order of removal.

Scheme 52

1. Verify that the continuity between the power MOS FET terminals is as indicated in the table. If there is any malfunction, replace the power MOS FET. If the blower motor operation is not normal even though no malfunction can be verified, inspect the climate control unit. (See «CLIMATE CONTROL UNIT INSPECTION [FULL-AUTO AIR CONDITIONER]»(ref-345245-S41100623352009102000000) ). TERMINALS RESISTANCE CHART Tester lead Resistance (kilohm) + - A B infinity A C 6.9 B A Continuity detected B C Continuity detected C A 6.9 C B infinity

Scheme 53

Scheme 54

Scheme 55

1. Remove the battery cover. (See «BATTERY REMOVAL/INSTALLATION [LF, L3]»(ref-345206-S36173522052009102000000) .)
2. Remove the following parts: Side wall (See «SIDE WALL REMOVAL/INSTALLATION»(ref-345251-S20393793122009102000000) .) Front scuff plate (LH) (See «FRONT SCUFF PLATE REMOVAL/INSTALLATION»(ref-345251-S03552764762009102000000) .) Front side trim (LH) (See «FRONT SIDE TRIM REMOVAL/INSTALLATION»(ref-345251-S39582742522009102000000) .) Hood release lever (See «HOOD LATCH AND RELEASE LEVER REMOVAL/INSTALLATION»(ref-345243-S34551921912009102000000) .) Lower panel (See «LOWER PANEL REMOVAL/INSTALLATION»(ref-345251-S05584420032009102000000) .) Column cover (See «COLUMN COVER REMOVAL/INSTALLATION»(ref-345251-S35932273802009102000000) .) Meter hood (See «METER HOOD REMOVAL/INSTALLATION»(ref-345251-S07110092202009102000000) .) Instrument cluster (See «INSTRUMENT CLUSTER REMOVAL/INSTALLATION»(ref-345262-S32996487732009102000000) .) Steering shaft (See «STEERING WHEEL AND COLUMN REMOVAL/INSTALLATION»(ref-345219-S02633973402009102000000) .) Accelerator pedal (See «ACCELERATOR PEDAL REMOVAL/INSTALLATION [L3 WITH TC]»(ref-345225-S27974467802009102000000) or «ACCELERATOR PEDAL REMOVAL/INSTALLATION [LF, L3]»(ref-345212-S01618660652009102000000) .) Brake pedal (See «BRAKE PEDAL REMOVAL/INSTALLATION»(ref-345233-S17425213882009102000000) .)
3. Disconnect the blower motor cooling pipe connected to the blower motor.
4. Disconnect the resistor connector.
5. Remove the resistor.
6. Affix the gummed tape to the thread hole area as shown in the figure. (Do not wrap the packing tape around the backside of the resistor.)
7. Stick the screw into the thread hole.
8. Set the resistor to the A/C unit and temporarily tighten the hexagon head screw. CAUTION: While setting the resistor, be careful not to damage the pattern surface. Otherwise it could cause a resistor operation malfunction.
9. Tighten the lower screw.
10. Tighten the hexagon head screw.
11. Connect the resistor connector.
12. Connect the blower motor cooling pipe.
13. Install the following parts: Brake pedal (See «BRAKE PEDAL REMOVAL/INSTALLATION»(ref-345233-S17425213882009102000000) Accelerator pedal (See «ACCELERATOR PEDAL REMOVAL/INSTALLATION [L3 WITH TC]»(ref-345225-S27974467802009102000000) or «ACCELERATOR PEDAL REMOVAL/INSTALLATION [LF, L3]»(ref-345212-S01618660652009102000000) .) Steering shaft (See «STEERING WHEEL AND COLUMN REMOVAL/INSTALLATION»(ref-345219-S02633973402009102000000) .) Instrument cluster (See «INSTRUMENT CLUSTER REMOVAL/INSTALLATION»(ref-345262-S32996487732009102000000) .) Meter hood (See «METER HOOD REMOVAL/INSTALLATION»(ref-345251-S07110092202009102000000) .) Column cover (See «COLUMN COVER REMOVAL/INSTALLATION»(ref-345251-S35932273802009102000000) .) Lower panel (See «LOWER PANEL REMOVAL/INSTALLATION»(ref-345251-S05584420032009102000000) .) Hood release lever (See «HOOD LATCH AND RELEASE LEVER REMOVAL/INSTALLATION»(ref-345243-S34551921912009102000000) .) Front side trim (LH) (See «FRONT SIDE TRIM REMOVAL/INSTALLATION»(ref-345251-S39582742522009102000000) .) Front scuff plate (LH) (See «FRONT SCUFF PLATE REMOVAL/INSTALLATION»(ref-345251-S03552764762009102000000) .) Side wall (See «SIDE WALL REMOVAL/INSTALLATION»(ref-345251-S20393793122009102000000) .)
14. Connect the negative battery cable.
15. Install the battery cover.

Scheme 56

1. Verify that the resistance between the resistor terminals is as shown in the table. If there is any malfunction, replace the resistor. TERMINALS RESISTANCE CHART Terminal Resistance (ohm) A-D 0.27-0.30 A-B 1.30-1.49 A-C 2.10-2.40

Scheme 57

1. Disassemble in the order indicated in the table.
2. Assemble in the reverse order of disassembly.
3. Adjust the magnetic clutch clearance. (See «MAGNETIC CLUTCH ADJUSTMENT»(ref-345245-S40272007792009102000000) ).

EVAPORATOR TEMPERATURE SENSOR INSPECTION

Note. Inspect the evaporator temperature sensor when it is installed to the A/C unit.

Scheme 58

1. Set the fan speed MAX HI.
2. Set the temperature control at MAX COLD.
3. Set the RECIRCULATE mode.
4. Turn the A/C switch off.
5. Close all doors and windows.
6. Wait for 5 min.
7. Disconnect the evaporator temperature sensor connector.
8. Measure the temperature at the blower inlet.
9. Measure the resistance between the evaporator temperature sensor terminals. If the resistance is not as shown in the graph, replace the evaporator temperature sensor.

Scheme 59

Scheme 60

1. Disconnect the negative battery cable.
2. Discharge the refrigerant from the system. (See «REFRIGERANT CHARGING»(ref-345268-S40252650632009102000000) .)
3. Remove the P/S fluid reserve tank. (L3 with TC)
4. Remove the coolant reserve tank. (L3 with TC)
5. Loosen the refrigerant pressure switch using two spanners.
6. Remove in the order indicated in the table. LF, L3 L3 with TC
7. Install in the reverse order of removal.

CLIMATE CONTROL UNIT INSPECTION [FULL-AUTO AIR CONDITIONER]

1. Turn the ignition switch to the ON position.
2. Connect the negative (-) lead of the tester to body ground.
3. By inserting the positive (+) lead of the tester into each climate control unit terminal, measure the voltage according to the terminal voltage table. If there is any malfunction, inspect the parts under "Inspection item (s)". If the parts under "Inspection item (s)" are found to be normal (except for terminal F), replace the climate control unit. For terminal F, first try replacing the power MOS FET. If there is still any malfunction, replace the climate control unit.

Scheme 61

CLIMATE CONTROL UNIT CONNECTOR TERMINAL VOLTAGE CHART

Scheme 62

CLIMATE CONTROL UNIT INSPECTION [MANUAL AIR CONDITIONER]

1. Install the PJB.
2. Turn the ignition switch to the ON position.
3. Connect the negative (-) lead of the tester to body ground.
4. By inserting the positive (+) lead of the tester into each climate control unit terminal, measure the voltage according to the terminal voltage table. If there is any malfunction, inspect the parts under "Inspection item (s)". If the parts under "Inspection item (s)" are found to be normal, replace the climate control unit.

Scheme 63

CLIMATE CONTROL UNIT CONNECTOR TERMINAL REFERENCE

Scheme 64

Scheme 65

Scheme 66

1. Set the temperature control dial at middle position (MAX HOT-MAX COLD).
2. Connect the air mix wire to air mix link.
3. Install the air mix wire to the wire clamp as shown in the figure.
4. Remove the screwdriver and verify that the temperature control dial can move its full stroke.

Scheme 67

1. Set the airflow mode selector dial at defroster.
2. Connect the airflow mode wire to airflow mode link.
3. Install the airflow mode wire to the wire clamp as shown in the figure.
4. Remove the screwdriver and verify that the airflow mode selector dial can move its full stroke.

Scheme 68

Scheme 69

1. Remove the climate control unit.
2. Verify that the continuity between the fan switch terminals is as indicated in the table. If there is any malfunction, replace the fan switch.