Mazda CX-9 Grand Touring. Manual — part 311

5



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



Access the PCM and monitor the TP1 and
TP2 PIDs.



Slowly press the accelerator pedal from fully
released to fully depressed while observing
the voltage readings.



Use the chart as a reference.



Inspect the TP sensor.

(See THROTTLE POSITION (TP)
SENSOR INSPECTION [MZI-3.7] .)



Do all signal values smoothly change when
the accelerator is depressed?

Yes Go to the next step.

No

Replace the throttle body. Then go to

Step 9.

6

INSPECT TP SENSOR CIRCUIT FOR
INTERMITTENT CONCERN



Access the PCM and monitor the TP1 and
TP2 PIDs.



Wiggle, shake, and bend the wiring harness
from the TP to the PCM.



Are the voltages between 0.49-4.65 V?

Yes Go to the next step.

No

Repair or replace suspected part, then go

to Step 9.

7

INSPECT THROTTLE ACTUATOR
CONTROL MOTOR VISUALLY



Turn the ignition switch off.



Inspect the throttle actuator control motor for
damaged housing, wiring harness connector,
and wiring harness.



Are there any concerns with the throttle
actuator control motor hardware?

NOTE:



Make sure the throttle body connector is
properly connected.

Yes

Replace the throttle body. Then go to
Step 9.

No

Go to the next step.

8

INSPECT THROTTLE ACTUATOR
CONTROL CIRCUITS FOR SHORT EACH
OTHER



Turn the ignition switch off.



Measure resistance between throttle actuator

Yes Go to the next step.

No

Repair or replace suspected part, then go

2008 Mazda CX-9 Grand Touring

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

Microsoft

Sunday, November 15, 2009 10:08:42 AM

Page 377

© 2005 Mitchell Repair Information Company, LLC.

DTC P2121, P2126, P2131 [MZI-3.7]

DTC P2121, P2126, P2131 (MZI-3.7) DETECTION CONDITIONS AND POSSIBLE CAUSES

terminal A and B.



Is the resistance more than 10 kilohms?

to the next step.

9

VERIFY TROUBLESHOOTING OF DTC
P2112 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 P2121

APP sensor No.1 circuit range/performance

DTC P2126

APP sensor No.2 circuit range/performance

DTC P2131

APP sensor No.3 circuit range/performance

DETECTION

CONDITION



APP sensor fault flag is set for sensor No.1, No.2 and No.3 by the PCM,
indicating the signal is out of the normal self-test operating range.



APP sensor signal circuits are shorted each other



APP sensor malfunction



PCM malfunction

P2121



Open circuit wiring harness between APP sensor terminal E and PCM
terminal 1AK



Short to ground circuit between APP sensor terminal E and PCM terminal 1
AK



Short to power supply in wiring harness between APP sensor terminal E
and PCM terminal 1 AK

2008 Mazda CX-9 Grand Touring

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

Microsoft

Sunday, November 15, 2009 10:08:42 AM

Page 378

© 2005 Mitchell Repair Information Company, LLC.

POSSIBLE CAUSE

P2126



Open circuit wiring harness between APP sensor terminal H and PCM
terminal 1AG



Short to ground circuit between APP sensor terminal H and PCM terminal
1 AG



Short to power supply in wiring harness between APP sensor terminal H
and PCM terminal 1 AG

P2131



Open circuit wiring harness between APP sensor terminal B and PCM
terminal 1 AC



Short to ground circuit between APP sensor terminal B and PCM terminal 1
AC



Short to power supply in wiring harness between APP sensor terminal B
and PCM terminal 1 AC

2008 Mazda CX-9 Grand Touring

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

Microsoft

Sunday, November 15, 2009 10:08:42 AM

Page 379

© 2005 Mitchell Repair Information Company, LLC.

DIAGNOSTIC PROCEDURE

DTC P2121, P2126, P2131 (MZI-3.7) DIAGNOSTIC PROCEDURE

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.

VERIFY RELATED REPAIR

Perform repair or diagnosis according to the

2008 Mazda CX-9 Grand Touring

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

Microsoft

Sunday, November 15, 2009 10:08:42 AM

Page 380

© 2005 Mitchell Repair Information Company, LLC.