Mazda CX-9 Grand Touring. Manual — part 213

Fig. 28: Identifying HO2S Connector
Courtesy of MAZDA MOTORS CORP.

CIRCUIT OPEN/SHORT INSPECTION

1. Disconnect the PCM connector. (See PCM REMOVAL/INSTALLATION [MZI-3.7].)

2. Inspect the following wiring harness for open or short (continuity check).

2008 Mazda CX-9 Grand Touring

2008 ENGINE Control System (MZI-3.7) - Mazda CX-9

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Fig. 29: Identifying PCM Warning Harness-Side Connector
Courtesy of MAZDA MOTORS CORP.

Open circuit



If there is no continuity, the circuit is open. Repair or replace the harness.



HO2S (RH) terminal A and PCM terminal 2J



HO2S (RH) terminal B and PCM terminal 2Y



HO2S (RH) terminal C and main relay No.2 terminal D



HO2S (RH) terminal D and PCM terminal 2AL



HO2S (LH) terminal A and PCM terminal 2E



HO2S (LH) terminal B and PCM terminal 2U



HO2S (LH) terminal C and main relay No.2 terminal D



HO2S (LH) terminal D and PCM terminal 2AL

Short circuit

2008 Mazda CX-9 Grand Touring

2008 ENGINE Control System (MZI-3.7) - Mazda CX-9

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Sunday, November 15, 2009 10:07:19 AM

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© 2005 Mitchell Repair Information Company, LLC.



If there is continuity, the circuit is shorted. Repair or replace the harness.



HO2S (RH) terminal A and power supply



HO2S (RH) terminal A and body ground



HO2S (RH) terminal B and power supply



HO2S (RH) terminal B and body ground



HO2S (RH) terminal C and body ground



HO2S (RH) terminal D and power supply



HO2S (LH) terminal A and power supply



HO2S (LH) terminal A and body ground



HO2S (LH) terminal B and power supply



HO2S (LH) terminal B and body ground



HO2S (LH) terminal C and body ground



HO2S (LH) terminal D and power supply

REAR HEATED OXYGEN SENSOR (HO2S) REMOVAL/INSTALLATION [MZI-
3.7]

HO2S (LH) REMOVAL/INSTALLATION

1. Disconnect the negative battery cable.

2. Disconnect the HO2S (LH) connector.

3. Remove the HO2S (LH) using the SST.

4. Install in the reverse order of removal.

NOTE:



If necessary, lubricate the HO2S (LH) with Penetrating and Lock
Lubricant loosen to aid in removal.

NOTE:



Apply a light coat of anti-seize lubricant to the threads of the HO2S.

2008 Mazda CX-9 Grand Touring

2008 ENGINE Control System (MZI-3.7) - Mazda CX-9

Microsoft

Sunday, November 15, 2009 10:07:19 AM

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© 2005 Mitchell Repair Information Company, LLC.

Fig. 30: View Of HO2S, SST & Torque Specifications
Courtesy of MAZDA MOTORS CORP.

HO2S (RH) REMOVAL/INSTALLATION

1. Disconnect the negative battery cable.

2. Remove the following part for easier access.

1. Remove the cowl panel. (See COWL PANEL REMOVAL/INSTALLATION .)

3. Disconnect the HO2S (RH) connector.

4. Remove the HO2S (RH) using the SST.

5. Install in the reverse order of removal.

Fig. 31: View Of HO2S, SST & Torque Specifications
Courtesy of MAZDA MOTORS CORP.

REAR HEATED OXYGEN SENSOR (HO2S) INSPECTION [MZI-3.7]

REAR HEATED OXYGEN SENSOR (HO2S) VOLTAGE INSPECTION

1. Warm up the engine to normal operating temperature.

2. Using the M-MDS, monitor the following:



Vehicle speed (PID: VSS)

NOTE:



If necessary, lubricate the HO2S (RH) with Penetrating and Lock
Lubricant loosen to aid in removal.

NOTE:



Apply a light coat of anti-seize lubricant to the threads of the HO2S.

NOTE:



Before performing the following inspection, make sure to follow the
procedure as indicated in the troubleshooting flowchart. (See HOW TO
USE THIS MANUAL .)

2008 Mazda CX-9 Grand Touring

2008 ENGINE Control System (MZI-3.7) - Mazda CX-9

Microsoft

Sunday, November 15, 2009 10:07:19 AM

Page 34

© 2005 Mitchell Repair Information Company, LLC.