Mazda X-5. Manual - part 40

 

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Mazda X-5. Manual - part 40

 

 

CONTROL SYSTEM 

01–40–33

01–40

A/C CUT-OFF CONTROL OUTLINE [LF]

E5U014000000N43

• Through energization and non-energization to the A/C relay (magnetic clutch) according to engine operation 

conditions, acceleration performance and engine reliability have been improved.

End Of Sie

A/C CUT-OFF CONTROL BLOCK DIAGRAM [LF]

E5U014000000N44

End Of Sie

A/C CUT-OFF CONTROL OPERATION [LF]

E5U014000000N45

• The PCM stops energization to the A/C relay when any of the following conditions are met:

A/C cut-off control operation conditions

End Of Sie

TR SWITCH (AT)

ECT SENSOR

CKP SENSOR

NEUTRAL SWITCH (MT)

CPP SWITCH (MT)

A/C RELAY

PCM

TP SENSOR NO.1, NO.2

APP SENSOR NO.1, NO.2

A/C AMPLIFER

REFRIGERANT PRESSURE 

SWITCH (HIGH, LOW)

E5U140ZT5009

Operation condition

A/C relay non-energization period

Purpose

At engine start

Approx. 4 s

Improved startability

At drive-away

Approx. 3 s

Improved drive-away 
performance

During acceleration (throttle valve opening angle 50% 
or more)

Approx. 5 s

Improved acceleration 
performance

When the engine coolant temperature is 113 

°C {235 

°F}

Repeatedly turns on and off every 10 s 

until the engine coolant temperature is 

less than approx. 110 

°C {230 °F}

Improved engine reliability

When the engine coolant temperature is 118 

°C {245 

°F} or more

Until the engine coolant temperature 

decreases to less than approx. 114 

°C 

{237 

°F}

Improved engine reliability

At high engine speed (engine speed 6,600 rpm or 
more)

Approx. 1 s

Improved engine speed 
stability

CONTROL SYSTEM 

01–40–34

ELECTRICAL FAN CONTROL OUTLINE [LF]

E5U014000000N46

• Through cooling of the radiator and condenser by operation of the cooling fan according to vehicle conditions, 

engine reliability and cooling performance have been improved.

• The electrical fan control includes the regular-driving cooling function and the after-cooling function.

• The regular-driving cooling function operates according to the engine conditions during the engine operation.

• The after-cooling function operates when the vehicle has stopped at high engine temperature (ignition switch 

off).

• After the ignition switch is turned off, a main relay on request is sent to operate the after-cooling function. (See 

01–40–11 MAIN RELAY CONTROL OPERATION [LF].)

End Of Sie

ELECTRICAL FAN CONTROL BLOCK DIAGRAM [LF]

E5U014000000N47

• The PCM determines the engine operation conditions based on input signals from the sensors, and sends a 

signal to the cooling fan relay No.1, No.2, No.3.

End Of Sie

ELECTRICAL FAN CONTROL OPERATION [LF]

E5U014000000N48

• When the operation conditions are met for each function, the PCM sends an operation signal to cooling fan 

relay No.1 or No.2/No.3 to operate the cooling fan motors.

• The rotation speed of the cooling fan motor is switched between three levels according to a combination of the 

cooling fan relays.

• The cooling fan motor operation switches in the order of stop, low speed, middle speed, and high speed, taking 

3 s for each operation while regular-driving cooling.

ECT SENSOR

VEHICLE SPEED SIGNAL

IGNITION SWITCH

COOLING FAN RELAY NO.2

PCM

TP SENSOR NO.1, NO.2

COOLING FAN RELAY NO.3

COOLING FAN RELAY NO.1

IAT SENSOR

REFRIGERANT PRESSURE 

SWITCH (MIDDLE)

A/C AMPLIFER

REFRIGERANT PRESSURE 

SWITCH (HIGH, LOW)

E5U140ZT5010

CONTROL SYSTEM 

01–40–35

01–40

Operation Conditions

End Of Sie

Function

Operation condition

Cooling fan 

motor rotation 

speed

Cooling fan relay

ECT

A/C 

amplifier

(A/C switch)

Refrigerant 

pressure 

switch

(high, low)

Vehicle speed

No.1

No.2

No.3

Regular-
driving cooling

Less than 100 

°C 

{212 

°F}

OFF

Stop

OFF

ON

OFF

More than 70 

km/h {44 mph}

45 —70 km/h 

{28—43 mph}

Low

ON

OFF

OFF

Less than 45 

km/h {27 mph}

Middle

ON

OFF

ON

ON

High

ON

100—108 

°C 

{213—226.4 

°F}

OFF

Middle

ON

OFF

ON

ON

High

ON

More than 108 

°C 

{227 

°F}

After-cooling

• When all the following conditions are met:

— Ignition switch: OFF

— Estimated maximum engine coolant temperature is high after 

engine stop

Low

ON

OFF

OFF

• When all the following conditions are met:

— Estimated maximum engine coolant temperature is the 

specified value or more even when operating at low rotation 
speed.

Middle

ON

OFF

ON

COOLING 
FAN RELAY 
NO.1

COOLING 
FAN RELAY 
NO.3

COOLING 
FAN RELAY
NO.2

TO PCM

TO PCM 

TO PCM 

B+

E5U140ZN5855

CONTROL SYSTEM 

01–40–36

STARTER CUT-OFF CONTROL OUTLINE [LF]

E5U014000000N49

• Theft deterrence has been improved by controlling energization to the starter relay according to an engine stop 

request signal from the immobilizer system.

End Of Sie

STARTER CUT-OFF CONTROL BLOCK DIAGRAM [LF]

E5U014000000N50

End Of Sie

STARTER CUT-OFF CONTROL OPERATION [LF]

E5U014000000N51

• The PCM stops energization of the starter relay according to an engine stop request from the immobilizer 

system.
When receiving engine stop request signal

— The PCM does not establish a ground to the starter circuit. Therefore, the starter motor does not rotate 

because there is no energization of the starter relay even if the ignition switch is turned to the START 
position, and the engine does not start.

When not receiving engine stop request signal

— The PCM establishes a ground to the starter circuit. Therefore, when the ignition switch is turned to the 

START position, the starter relay is energized and the starter motor rotates. As a result, the engine starts 
normally.

End Of Sie

INSTRUMENT CLUSTER 

(IMMOBILIZER RELATED 

INFORMATION)

STARTER RELAY

PCM

E5U140ZW5403

PCM

M

WHEN NOT RECEIVING ENGINE 
STOP REQUEST SIGNAL

WHEN ENGINE STOP REQUEST 
SIGNAL IS RECEIVED

IGNITION 
SWITCH

START 
SIGNAL

STARTER 
RELAY

STARTER

AT

TR SWITCH

STARTER 
SWITCH

MT

IG 1

B+

PCM

M

IGNITION 

SWITCH

START 
SIGNAL

STARTER 
RELAY

STARTER

AT

TR SWITCH

STARTER 
SWITCH

MT

IG 1

B+

E5U140ZT5200

 

 

 

 

 

 

 

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