Mazda CX-9 Grand Touring. Manual - part 303

DTC P1501 [MZI-3.7] 

DTC P1501 (MZI-3.7) DETECTION CONDITIONS AND POSSIBLE CAUSES 

DIAGNOSTIC PROCEDURE 

DTC P1501 (MZI-3.7) DIAGNOSTIC PROCEDURE 

4



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?  

No

Go to the next step.

5

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 P1501

Vehicle speed sensor (VSS) out of self-test range

DETECTION 

CONDITION 



Indicates that the vehicle speed input signal is out of the self-test range. If the 
PCM detects a vehicle speed input signal any time during the self-test, DTC 
P1501 is set and the test aborts.  

POSSIBLE 

CAUSE 



Noise on the vehicle speed input signal from radio frequency 
interference/electro magnetic interference  



External sources, such as ignition wires, the charging circuit, or aftermarket 
equipment  

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 

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.

 

2008 Mazda CX-9 Grand Touring 

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

  

Microsoft 

 

Sunday, November 15, 2009 10:08:41 AM

Page 345 

© 2005 Mitchell Repair Information Company, LLC. 

DTC P1633 [MZI-3.7] 

DTC P1633 (MZI-3.7) DETECTION CONDITIONS AND POSSIBLE CAUSES 

available?  

3

VERIFY STORED DTC IN DSC/RSC 
HU/CM  



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



Verify stored DTCs in DSC/RSC 
HU/CM.  



Are DTCs stored?  

Yes

Go to the appropriate DTC inspection. (See 
ON-BOARD DIAGNOSIS [DSC/RSC] .)

No

Go to the next step.

4

VERIFY TROUBLESHOOTING OF 
DTC P1501 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.

5

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 P1633

Keep alive power voltage too low

DETECTION CONDITION 



Indicates the keep alive power circuit has experienced a voltage 
interrupt.  

POSSIBLE CAUSE 



Connector or terminal malfunction  



Open circuit between battery positive terminal and PCM terminal 1 
BB  

 

2008 Mazda CX-9 Grand Touring 

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

  

Microsoft 

 

Sunday, November 15, 2009 10:08:41 AM

Page 346 

© 2005 Mitchell Repair Information Company, LLC. 

DIAGNOSTIC PROCEDURE 

DTC P1633 (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 

 

2008 Mazda CX-9 Grand Touring 

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

  

Microsoft 

 

Sunday, November 15, 2009 10:08:41 AM

Page 347 

© 2005 Mitchell Repair Information Company, LLC. 



Has FREEZE FRAME DATA been 
recorded?  

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 BATTERY TERMINAL AND 
PCM CONNECTOR FOR POOR 
CONNECTION  



Turn the ignition switch off.  



Disconnect battery terminal and PCM 
connector.  



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



Is there any malfunction?  

Yes

Repair or replace suspected part, then go to 
Step 5.

No

Go to the next step.

4

INSPECT KEEP ALIVE POWER 
CIRCUIT FOR OPEN CIRCUIT  



Turn the ignition switch off.  



Disconnect battery cables.  



Disconnect PCM connector.  



Check continuity between battery 
positive terminal (harness-side) and 
PCM terminal 1BB (wiring harness-
side).  



Is there continuity?  

Yes Go to the next step.

No

Repair or replace suspected part, then go to the 

next step.

5

VERIFY TROUBLESHOOTING OF DTC 
P1633 HAS BEEN COMPLETED  



Make sure to reconnect all 
disconnected connectors.  



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



Start the engine.  



Is the same 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.

6

VERIFY AFTER REPAIR PROCEDURE 



Perform the "AFTER REPAIR 
PROCEDURE". (See AFTER 

Yes

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

 

2008 Mazda CX-9 Grand Touring 

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

  

Microsoft 

 

Sunday, November 15, 2009 10:08:41 AM

Page 348 

© 2005 Mitchell Repair Information Company, LLC.