Mazda 6. Manual - part 130

CONTROL SYSTEM 

F–48–8

4F

Cooling fan control

Cooling fan relay

Idling

ECT below 100 

°C {212 °F}

B+

• Inspect cooling fan 

relay

• Inspect related 

harness

A/C operating 
and refrigerant 
pressure switch 
(middle) ON

Below 1.0

4G

IAC (+)

IAC valve

• Inspect using the wave profile.

(See 

F–48–10 Inspection Using An 

Oscilloscope (Reference)

.)

• Inspect IAC valve

(See 

F–13 IDLE AIR 

CONTROL (IAC) 
VALVE INSPECTION

)

• Inspect related 

harness

4H

EGR valve #2 coil 
control

EGR valve 
(terminal A)

Ignition switch ON

B+

• Inspect EGR valve

(See 

F–40 EGR 

VALVE INSPECTION

)

• Inspect related 

harness

Idle

B+

4I

Starter relay control

Starter relay*

1

TR switch*

2

Under any condition

Below 1.0

• Perform “On-Board 

Diagnostic Test”
(See 

F–62 

ON-BOARD 
DIAGNOSTIC TEST

)

• Inspect related 

harness

4J

IAC (–)

IAC  valve

• Inspect using the wave profile.

(See 

F–48–10 Inspection Using An 

Oscilloscope (Reference)

.)

• Inspect IAC valve

(See 

F–13 IDLE AIR 

CONTROL (IAC) 
VALVE INSPECTION

)

• Inspect related 

harness

4K

EGR valve #3 coil 
control

EGR valve 
(terminal B)

Ignition switch ON

B+

• Inspect EGR valve

(See 

F–40 EGR 

VALVE INSPECTION

)

• Inspect related 

harness

Idle

B+

4L

Cooling fan control

Cooling fan relay

Idling

ECT below 100 

°C {212 °F}

B+

• Inspect cooling fan 

relay

• Inspect related 

harness

A/C operating

Below 1.0

4M*

4

OCV control

OCV

• Inspect using the wave profile.

(See 

F–48–10 Inspection Using An 

Oscilloscope (Reference)

.)

• Inspect OCV valve

(See 

B–33 OIL 

CONTROL VALVE 
(OCV) INSPECTION

)

• Inspect related 

harness

4N

EGR valve #4 coil 
control

EGR valve 
(terminal F)

Ignition switch ON

Below 1.0

• Inspect EGR valve

(See 

F–40 EGR 

VALVE INSPECTION

)

• Inspect related 

harness

Idle

Below 1.0

4O

A/C

A/C relay

A/C operating

Below 1.0

• Inspect A/C relay

• Inspect related 

harness

A/C not operating

B+

4P*

7

Fuel pump control

Fuel pump relay

Ignition switch ON

B+

• Inspect fuel pump 

relay

• Inspect related 

harness

Cranking

Below 1.0

Idle

Below 1.0

4Q*

6

Fuel pump control

Fuel pump relay

Ignition switch ON

B+

• Inspect fuel pump 

relay

• Inspect related 

harness

Cranking

Below 1.0

Idle

Below 1.0

Terminal

Signal

Connected to

Test condition

Voltage 

(V)

Action

CONTROL SYSTEM 

F–48–9

F

4R*

4

VIS control

VIS control 
solenoid valve

Engine speed: above 4,500 rpm

B+

• Inspect VIS solenoid 

valve
(See 

F–14 VARIABLE 

INTAKE-AIR SYSTEM 
(VIS) CONTROL 
SOLENOID VALVE 
INSPECTION (L3)

)

• Inspect related 

harness

Engine speed: below 4,500 rpm

Below 1.0

4S

—

—

—

—

—

4T

Variable tumble 
control

Variable tumble 
control solenoid 
valve

ECT above 63 

°C { 145 °F} while 

idling.

B+

• Inspect VIS solenoid 

valve
(See 

F–15 VARIABLE 

TUMBLE CONTROL 
SOLENOID VALVE 
INSPECTION

)

• Inspect related 

harness

ECT below 63 

°C {145 °F} and 

engine speed below 3,750 rpm

Below 1.0

4U

Purge control

Purge solenoid 
valve

• Inspect using the wave profile.

(See 

F–48–10 Inspection Using An 

Oscilloscope (Reference)

.)

• Inspect purge 

solenoid valve
(See 

F–39 PURGE 

SOLENOID VALVE 
INSPECTION

)

• Inspect related 

harness

4V*

2

B+

Main relay

Ignition switch OFF

Below 1.0

• Inspect battery

• Inspect related 

harness

Ignition switch ON

B+

4W

Fuel injection (#2)

Fuel injector No.2

• Inspect using the wave profile.

(See 

F–48–10 Inspection Using An 

Oscilloscope (Reference)

.)

• Inspect fuel injector 

No.2
(See 

F–31 FUEL 

INJECTOR 
INSPECTION

)

• Inspect related 

harness

4X

GND

GND

Under any condition

Below 1.0

• Inspect related 

harness

4Y*

2

Shift solenoid C 
control

Shift solenoid C

• Inspect using the wave profile.

(See 

F–48–10 Inspection Using An 

Oscilloscope (Reference)

.)

• Inspect shift solenoid 

C

• Inspect related 

harness

4Z

Fuel injection (#1)

Fuel injector No.1

• Inspect using the wave profile.

(See 

F–48–10 Inspection Using An 

Oscilloscope (Reference)

.)

• Inspect fuel injector 

No.1
(See 

F–31 FUEL 

INJECTOR 
INSPECTION

)

• Inspect related 

harness

4AA

Fuel injection (#4)

Fuel injector No.4

• Inspect using the wave profile.

(See 

F–48–10 Inspection Using An 

Oscilloscope (Reference)

.)

• Inspect fuel injector 

No.4
(See 

F–31 FUEL 

INJECTOR 
INSPECTION

)

• Inspect related 

harness

4AB*

2

Shift solenoid A 
control

Shift solenoid A

• Inspect using the wave profile.

(See 

F–48–10 Inspection Using An 

Oscilloscope (Reference)

.)

• Inspect shift solenoid 

A

• Inspect related 

harness

4AC*

2

Shift solenoid B 
control

Shift solenoid B

• Inspect using the wave profile.

(See 

F–48–10 Inspection Using An 

Oscilloscope (Reference)

.)

• Inspect shift solenoid 

B

• Inspect related 

harness

Terminal

Signal

Connected to

Test condition

Voltage 

(V)

Action

CONTROL SYSTEM 

F–48–10

*

1

: MTX models

*

2

: ATX models

*

3

: LF, L8 engine models

*

4

: L3 engine models

*

5

: MTX, without ABS models

*

6

: Immobilizer system equipped

*

7

: Immobilizer system not equipped

Inspection Using An Oscilloscope (Reference)
IGT1, IGT2 control signals
PCM terminals

• IGT1(No.1 and No.4): 1A(+)—1D(–)

• IGT2(No.2 and No.3): 1B(+)—1C(–)

Oscilloscope setting

• 4 V/DIV (Y), 0.01 ms/DIV (X), DC range

Vehicle condition

• Idle after warm up (engine speed approx. 650 

rpm [MTX] or 700 rpm [ATX], no load, P/S off, A/C 
off)

Generator output voltage signal
PCM terminals

• 1AA(+)—2AC(–)

Oscilloscope setting

• 2 V/DIV (Y), 2 ms/DIV (X), DC range

Vehicle condition

• Idle after warm up (engine speed approx. 650 

rpm [MTX] or 700 rpm [ATX], no load, P/S off, A/C 
off)

HO2S (front) signal
PCM terminals

• 1AB(+)—2H(–)

Oscilloscope setting

• 0.1 V/DIV (Y), 400 ms/DIV (X), DC range

Vehicle condition

• Idle after warm up (engine speed approx. 650 

rpm [MTX], 700 rpm [ATX], no load, P/S off, A/C 
off)

4AD

Fuel injection (#3)

Fuel injector No.3

• Inspect using the wave profile.

(See 

F–48–10 Inspection Using An 

Oscilloscope (Reference)

.)

• Inspect fuel injector 

No.3
(See 

F–31 FUEL 

INJECTOR 
INSPECTION

)

• Inspect related 

harness

Terminal

Signal

Connected to

Test condition

Voltage 

(V)

Action

0 V

A6A3940W003

0 V

A6A3940W004

0 V

A6A3940W005

CONTROL SYSTEM 

F–48–11

F

Generator field coil control signal
PCM terminals

• 1AD(+)—1C(–)

Oscilloscope setting

• 0.5 V/DIV (Y), 1 ms/DIV (X), DC range

Vehicle condition

• Idle after warm up (engine speed approx. 650 

rpm [MTX] or 700 rpm [ATX], no load, P/S off, A/C 
off)

CKP sensor signal
(+)
PCM terminals

• 2D(+)—2H(–)

Oscilloscope setting

• 2 V/DIV (Y), 4 ms/DIV (X), DC range

Vehicle condition

• Idle after warm up (engine speed approx. 650 

rpm [MTX] or 700 rpm [ATX], no load, P/S off, A/C 
off)

(–)
PCM terminals

• 2G(+)—2H(–)

Oscilloscope setting

• 2 V/DIV (Y), 4 ms/DIV (X), DC range

Vehicle condition

• Idle after warm up (engine speed approx. 650 

rpm [MTX] or 700 rpm [ATX], no load, P/S off, A/C 
off)

VSS signal
PCM terminals

• 3C(+)—2AC(–)

Oscilloscope setting

• 1 V/DIV (Y), 10 ms/DIV (X), DC range

Vehicle condition

• Drive the vehicle with approx. 10 km/h {6.2 mph}

0 V

A6A3940W006

0 V

A6A3940W007

0 V

A6A3940W008

0 V

A6A3940W011