Mazda CX-9 Grand Touring. Manual — part 289

STEP

INSPECTION

ACTION

1

VERIFY FREEZE FRAME DATA HAS
BEEN RECORDED



Has FREEZE FRAME DATA been
recorded?

Yes Go to the next step.

No

Record FREEZE FRAME DATA on the

repair order, then go to the next step.

2

VERIFY RELATED REPAIR
INFORMATION AVAILABILITY



Verify related Service Bulletins and/or
on-line repair information availability.



Is any related Service Bulletins
available?

Yes

Perform repair or diagnosis according to the
available Service Bulletins.



If the vehicle is not repaired, go to the
next step.

No

Go to the next step.

3

INSPECT GENERATOR TERMINAL
FOR POOR INSTALLATION



Turn the engine switch off.



Inspect generator terminal B for
looseness.



Are there any malfunction?

Yes

Connect generator terminal B correctly, then
go to Step 9.

No

Go to the next step.

4

INSPECT GENERATOR CIRCUIT FOR
SHORT TO POWER SUPPLY



Turn the ignition switch to the ON
position (Engine off).



Measure the voltage between the
following terminals:



Generator terminal RC (wiring
harness-side) and body ground.



Generator terminal LI (wiring
harness-side) and body ground.



Is the voltage B+?

Yes

Repair or replace suspected part, then go to
Step 9.

No

Go to the next step.

5

INSPECT PCM CONNECTOR FOR
POOR CONNECTION



Turn the engine switch off.



Inspect for poor connection (such as
damaged/pulled-out terminals,
corrosion).



Are there any malfunction?

Yes

Repair or replace suspected part, then go to
Step 9.

No

Go to the next step.

INSPECT GENERATOR CIRCUIT FOR
OPEN CIRCUIT



Inspect for continuity between generator

Yes Go to the next step.

2008 Mazda CX-9 Grand Touring

2008 ENGINE PERFORMANCE On-Board Diagnostic (MZI-3.7) - Mazda CX-9

Microsoft

Sunday, November 15, 2009 10:08:40 AM

Page 289

© 2005 Mitchell Repair Information Company, LLC.

DTC P0642 [MZI-3.7]

DTC P0642 (MZI-3.7) DETECTION CONDITIONS AND POSSIBLE CAUSES

6

terminal RC (wiring harness-side) and
PCM terminal 2S (wiring harness-side).



Is there continuity?

No

Repair or replace suspected part, then go to

Step 9.

7

INSPECT BATTERY POSITIVE
TERMINAL FOR POOR INSTALLATION



Turn the engine switch off.



Inspect the battery positive terminal for
looseness.



Is there any malfunction?

Yes

Connect the battery positive terminal
correctly, then go to Step 9.

No

Go to the next step.

8

INSPECT GENERATOR CIRCUIT FOR
OPEN CIRCUIT



Inspect the continuity between generator
terminal B (wiring harness-side) and
battery positive terminal (wiring
harness-side)



Is there continuity?

Yes Go to the next step.

No

Repair or replace suspected part, then go to

the next step.

9

VERIFY TROUBLESHOOTING OF DTC
P0626 HAS BEEN COMPLETED



Verify that all disconnected connectors
reconnected.



Clear the DTC from the PCM memory
using the M-MDS.



Perform the KOEO or KOER self-test
using the M-MDS. (See KOEO/KOER
SELF TEST [MZI-3.7].)



Is the PENDING CODE for the DTC
present?

Yes

Replace the PCM, then go to the next step.
(See PCM REMOVAL/INSTALLATION
[MZI-3.7] .)

No

Go to the next step.

10

VERIFY AFTER REPAIR PROCEDURE



Perform the "AFTER REPAIR
PROCEDURE". (See AFTER REPAIR
PROCEDURE [MZI-3.7].)



Are any DTCs present?

Yes

Go to the applicable DTC inspection. (See
DTC TABLE [MZI-3.7].)

No

Troubleshooting completed.

DTC P0642

Sensor reference voltage circuit low

DETECTION

CONDITION



Indicates the reference voltage circuit is lower than reference voltage
minimum.

2008 Mazda CX-9 Grand Touring

2008 ENGINE PERFORMANCE On-Board Diagnostic (MZI-3.7) - Mazda CX-9

Microsoft

Sunday, November 15, 2009 10:08:40 AM

Page 290

© 2005 Mitchell Repair Information Company, LLC.

DIAGNOSTIC PROCEDURE

DTC P0642 (MZI-3.7) DIAGNOSTIC PROCEDURE

POSSIBLE CAUSE



Short to ground between fuel tank pressure sensor terminal C and PCM
terminal 1U



Fuel tank pressure sensor malfunction



Connector or terminal malfunction

STEP

INSPECTION

ACTION

VERIFY FREEZE FRAME DATA

Yes Go to the next step.

2008 Mazda CX-9 Grand Touring

2008 ENGINE PERFORMANCE On-Board Diagnostic (MZI-3.7) - Mazda CX-9

Microsoft

Sunday, November 15, 2009 10:08:40 AM

Page 291

© 2005 Mitchell Repair Information Company, LLC.

1

HAS BEEN RECORDED



Has FREEZE FRAME DATA been
recorded?

No

Record FREEZE FRAME DATA on the repair

order, then go to the next step.

2

VERIFY RELATED REPAIR
INFORMATION AVAILABILITY



Verify related Service Bulletins
and/or on-line repair information
availability.



Is any related Service Bulletins
available?

Yes

Perform repair or diagnosis according to the
available Service Bulletins.



If the vehicle is not repaired, go to the next
step.

No

Go to the next step.

3

INSPECT FUEL TANK PRESSURE
SENSOR CONNECTOR FOR POOR
CONNECTION



Turn the ignition switch off.



Disconnect the fuel tank pressure
sensor connector.



Inspect for poor connection (such as
damaged/pulled-out pins,
corrosion).



Are there any malfunction?

Yes Repair or replace suspected part, then go to Step 7.

No

Go to the next step.

4

INSPECT PCM CONNECTOR FOR
POOR CONNECTION



Turn the ignition switch off.



Disconnect the PCM connector.



Inspect for poor connection (such as
damaged/pulled-out pins,
corrosion).



Are there any malfunction?

Yes Repair or replace suspected part, then go to Step 7.

No

Go to the next step.

5

INSPECT FUEL TANK PRESSURE
SENSOR CIRCUIT FOR SHORT TO
GROUND



Turn the ignition switch off.



Inspect the continuity between fuel
tank pressure sensor terminal C
(wiring harness-side) and body
ground.



Is there continuity?

Yes Repair or replace suspected part, then go to Step 7.

No

Go to the next step.

INSPECT FUEL TANK PRESSURE
SENSOR

2008 Mazda CX-9 Grand Touring

2008 ENGINE PERFORMANCE On-Board Diagnostic (MZI-3.7) - Mazda CX-9

Microsoft

Sunday, November 15, 2009 10:08:40 AM

Page 292

© 2005 Mitchell Repair Information Company, LLC.