Mazda CX-9 Grand Touring. Manual — part 331

12

Connect the M-MDS to the DLC-2.
Turn the ignition switch to the ON position
(Engine off).
Retrieve any DTCs.
Are there any DTCs displayed?

Yes

DTC is displayed:
Go to appropriate DTC inspection.
(See DTC TABLE [MZI-3.7] .)
Communication error message is
displayed:
Inspect for the following:



Open circuit in wiring harness
between main relay and PCM
terminal 1 BO or 1BJ



Open main relay GND circuit



Main relay is stuck open.



Open or short circuit in wiring
harness between the DLC-2 and
PCM terminals 1BL or 1BG



Open or poor GND circuit (PCM
terminal 1D, 1J, 1BP, 1BK)



Poor connection of vehicle body
GND

No

No DTC is displayed:

Go to the next step.

13

Attempt to start engine at part throttle.
Does engine run smoothly at part throttle?

Yes

Inspect electronic throttle control system
operation.
(See ENGINE CONTROL SYSTEM
OPERATION INSPECTION [MZI-
3.7].)

No

Go to the next step.

14

Connect the M-MDS to the DLC-2.
Access RPM PID.
Is RPM PID indicating engine speed
during engine cranking?

Yes

Go to the next step.

No

Inspect for the following:



Open or short circuit in CKP sensor



Open or short circuit in wiring

harness between CKP sensor

terminal A and PCM terminal 2P



Open or short circuit in wiring

harness between CKP sensor

terminal B and PCM terminal 2T



Open or short circuit in CKP sensor

wiring harnesses

If CKP sensor and wiring harness are

normal, go to the next step.

Visually inspect CKP sensor and teeth of

2008 Mazda CX-9 Grand Touring

2008 ENGINE Symptom Troubleshooting (MZI-3.7) - Mazda CX-9

Microsoft

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15

crankshaft pulley.
Are CKP sensor and teeth of crankshaft
pulley normal?

Yes

Go to the next step.

No

Replace the malfunctioning part.

16

Inspect the ignition coil related wiring
harness condition (intermittent open or
short circuit) for all cylinders. Are wiring
harness conditions normal?

Yes

Go to the next step.

No

Repair the wiring harnesses.

17

Perform the spark test.
(See ENGINE CONTROL SYSTEM
OPERATION INSPECTION [MZI-
3.7].)
Is strong blue spark visible at each
cylinder?

Yes

Go to the next step.
If symptoms occurs with the A/C on, go to
Step 23.

No

Repair or replace the malfunctioning part

according to spark test result.

18

Inspect the spark plug condition.
Is spark plug wet, covered with carbon or
grayish white?

Yes

Spark plug is wet or covered with
carbon:
Inspect for fuel leakage from injector.
Spark plug is grayish white:
Inspect the fuel injector for clogging.

No

Install spark plugs on original cylinders.

Go to the next step.

19

Remove and shake the PCV valve.
Does the PCV valve rattle?

Yes

Go to the next step.

No

Replace the PCV valve.

20

visually inspect the exhaust system part.
Is there any deformed exhaust system part?

Yes

Replace the suspected part.

No

Go to the next step.

21

Install the fuel pressure gauge between the
fuel pipe and the fuel distributor.
Short check connector terminal F/P to body
GND using a jumper wiring.
Turn the ignition switch to the ON
position.
Is fuel line pressure correct with ignition
switch ON?
(See FUEL LINE PRESSURE
INSPECTION [MZI-3.7] .)

Yes

Go to the next step.

No

Zero or low:

Inspect the fuel pump relay and fuel pump

circuit.

Inspect the fuel line for clogging.

If there is no malfunction, replace the fuel

pump unit.

(See FUEL PUMP UNIT

REMOVAL/INSTALLATION [MZI-

3.7] .)
High:

Replace the fuel pump unit.

(See FUEL PUMP UNIT

REMOVAL/INSTALLATION [MZI-

3.7] .)

22

Visually inspect for fuel leakage at fuel
injector O-ring and fuel line.
Service if necessary.
Is fuel line pressure held after ignition
switch is turned off?
(See FUEL LINE PRESSURE

Yes

Go to the next step.

No

Inspect the fuel injector.

If the fuel injector is normal, replace the

fuel pump unit.

(See FUEL PUMP UNIT

REMOVAL/INSTALLATION [MZI-

2008 Mazda CX-9 Grand Touring

2008 ENGINE Symptom Troubleshooting (MZI-3.7) - Mazda CX-9

Microsoft

Sunday, November 15, 2009 10:10:05 AM

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© 2005 Mitchell Repair Information Company, LLC.

INSPECTION [MZI-3.7] .)

3.7] .)

23

Connect pressure gauges to A/C low and
high pressure side lines.Turn A/C on and
measure low side and high side
pressures.Are pressures within
specifications?(See REFRIGERANT
PRESSURE CHECK .)

NOTE:



The following test is for stall
concerns with the A/C on. If other
symptoms exist, go to the next
step.

Yes

Go to the next step.

No

If A/C is always on, go to symptom

troubleshooting "No.24 A/C is always on

or A/C compressor runs continuously".

(See NO.24 A/C IS ALWAYS ON OR

A/C COMPRESSOR RUNS

CONTINUOUSLY [MZI-3.7].)

For other symptoms, inspect the following:



Refrigerant charging amount



Condenser fan operation

24

Disconnect the vacuum hose between the
purge solenoid valve and the intake
manifold from purge solenoid side.
Plug opening end of vacuum hose.
Start the engine.
Is the engine stall now eliminated?

Yes

Inspect if purge solenoid valve is stuck
open.
Inspect evaporative emission control
system.

No

Go to the next step.

25

Is air leakage felt or heard at intake-air
system components while racing the
engine to higher speed?

Yes

Repair or replace the malfunctioning part.

No

Go to the next step.

26

Inspect variable valve timing control
system operation.
(See ENGINE CONTROL SYSTEM
OPERATION INSPECTION [MZI-
3.7].)
Does variable valve timing control
function properly?

Yes

Go to the next step.

No

Repair or replace the malfunctioning parts

according to variable valve timing control

system operation inspection results.

27

Is the engine compression correct?

Yes

Inspect the valve timing.

No

Inspect for cause.

28



Verify test results.



If normal, return to diagnostic index to service any additional symptoms.

(See SYMPTOM DIAGNOSTIC INDEX [MZI-3.7].)



If malfunction remains, inspect related Service Bulletins and/or On-line Repair
Information and perform repair or diagnosis.



If vehicle is repaired, troubleshooting completed.



If vehicle is not repaired or additional diagnostic information is not available,
replace the PCM.

(See PCM REMOVAL/INSTALLATION [MZI-3.7] .)

2008 Mazda CX-9 Grand Touring

2008 ENGINE Symptom Troubleshooting (MZI-3.7) - Mazda CX-9

Microsoft

Sunday, November 15, 2009 10:10:05 AM

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© 2005 Mitchell Repair Information Company, LLC.

NO.6 CRANKS NORMALLY BUT WILL NOT START [MZI-3.7]

NO.6 CRANKS NORMALLY BUT WILL NOT START (MZI-3.7) DETECTION CONDITIONS AND
POSSIBLE CAUSES

6

CRANKS NORMALLY BUT WILL NOT START

DESCRIPTION



The starter cranks engine at normal speed but the engine will not run.



Refer to symptom troubleshooting "NO.5 ENGINE STALLS" if this symptom
appears after engine stall.



Fuel is in tank.



Battery is in normal condition.

POSSIBLE

CAUSE



No battery power supply to PCM



Air leakage from intake-air system



Open PCM GND or vehicle body GND



Improper operation of electronic throttle control system



No signal from CKP sensor due to sensor, related wire or incorrect installation



No signal from CMP sensor due to sensor, related wire or incorrect installation



Low engine compression



Engine overheating



Vacuum leakage



Erratic signal to ignition coil



Improper air/fuel mixture ratio control



Poor fuel quality



PCV valve malfunction



Restriction in intake-air system



Restriction in exhaust system



Disconnected electrical connector



Open or short circuit in fuel pump body and related wiring harness



Inadequate fuel pressure



Fuel pump mechanical malfunction



Fuel leakage from injector



Fuel injector is clogged.



Purge solenoid valve malfunction



Spark plug malfunction



Ignition coil malfunction



Improper variable valve timing control system operation



Improper valve timing



Immobilizer system and/or circuit malfunction



Immobilizer system operating properly. (Ignition key is not registered.)

2008 Mazda CX-9 Grand Touring

2008 ENGINE Symptom Troubleshooting (MZI-3.7) - Mazda CX-9

Microsoft

Sunday, November 15, 2009 10:10:05 AM

Page 33

© 2005 Mitchell Repair Information Company, LLC.