Mazda CX-9 Grand Touring. Manual - part 310

and release.  



Does the throttle plate move freely to wide 
open and back?  

5

INSPECT TP SENSOR OPERATION  



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.

INSPECT THROTTLE ACTUATOR 
CONTROL CIRCUITS FOR SHORT EACH 
OTHER  

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 10:08:42 AM

Page 373 

© 2005 Mitchell Repair Information Company, LLC. 

DTC P2112 [MZI-3.7] 

DTC P2112 (MZI-3.7) DETECTION CONDITIONS AND POSSIBLE CAUSES 

8



Turn the ignition switch off.  



Disconnect the throttle body and PCM 
connector.  



Measure resistance between throttle actuator 
terminal A and B.  



Is the resistance more than 10 kilohms?  

No

Repair or replace suspected part, then go 

to the next step.

9

VERIFY TROUBLESHOOTING OF DTC 
P2111 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 P2112

Throttle actuator control system - stuck closed

DETECTION 

CONDITION 



This PCM fault status indicates the throttle plate is at a lower angle than 
commanded.  

POSSIBLE CAUSE 



Binding throttle body, stuck open  



Throttle actuator control circuits are cross-wired  



Throttle actuator control circuits are shorted each other  



PCM malfunction  

 

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 374 

© 2005 Mitchell Repair Information Company, LLC. 

DIAGNOSTIC PROCEDURE 

DTC P2112 (MZI-3.7) DIAGNOSTIC PROCEDURE 

STEP

INSPECTION

ACTION

1

VERIFY FREEZE FRAME DATA HAS BEEN 
RECORDED  

Yes Go to the next step.

No

Record FREEZE FRAME DATA on the 

repair order, then 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 10:08:42 AM

Page 375 

© 2005 Mitchell Repair Information Company, LLC. 



Has FREEZE FRAME DATA been recorded? 

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 THROTTLE POSITION OPEN 
CIRCUIT AND CLOSED VOLTAGES  



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



Access the PCM and monitor the TP1 and 
TP2 PIDs.  



Verify the following values of the PIDs when 
depressing the accelerator pedal to the floor 
and releasing. 



Pedal fully released: TP1 is 3.7-4.7 V  



Pedal fully released: TP2 is 0.3-1.9 V  



Pedal fully depressed: TP1 is 0.7-2.9 V 



Pedal fully depressed: TP2 is 4.1-4.7 V 



Are both PIDs within the specification?  

Yes Go to the Step 5.

No

Go to the next step.

4

INSPECT FOR OBSTRUCTION OF 
THROTTLE BODY 

 



Turn the ignition switch off.  



Remove the air hose from the throttle body.  



Visually inspect for throttle plate obstructions 
or sludge.  



Slowly, push the throttle plate to wide open 
and release.  



Does the throttle plate move freely to wide 
open and back?  

WARNING:



Substantial opening and closing torque is 
applied by this system. To prevent injury, 
be careful to keep fingers away from 
throttle mechanism when actuated. Failure 
to follow these instructions may result in 
personal injury.  

Yes Go to the Step 7.

No

Isolate and repair the obstruction. Then 

go to Step 9.

INSPECT TP SENSOR OPERATION  

 

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 376 

© 2005 Mitchell Repair Information Company, LLC.