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Home >> Mazda >> 2016 >> CX-9 Signature >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Heated Oxygen Sensor (Ho2S) Removal/Installation
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Heated Oxygen Sensor (Ho2S) Removal/Installation

Special Service Tool (SST) 

1.: Mazda SST number
2.: Global SST number
1:49 L018 001
2: -
O2 sensor wrench
G10947142Courtesy of MAZDA MOTORS CORP.
WARNING:
  • A hot engine and exhaust system can cause severe burns. Turn off the engine and wait until they are cool before removing the exhaust system.
CAUTION:
  • Do not allow flammable objects such as the taping for bundling the wiring harness to come into contact with the exhaust system such as the exhaust manifold and silencer which reach high temperatures. Otherwise, it could cause fire damage.
NOTE:
  • If penetrant lubricating spray penetrates the airflow hole of the HO2S, it could cause interference with the HO2S function.
  • When removing the HO2S, wrap a rag around the lower position so that penetrant lubricating spray does not get sprayed into the airflow hole.
G10947143Courtesy of MAZDA MOTORS CORP.

2WD 

G10947144Courtesy of MAZDA MOTORS CORP.
  1. Disconnect the negative battery terminal. (Refer to NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION .)
  2. Lift up the vehicle.
  3. Remove the following parts:
    1. Plate (Refer to EXHAUST SYSTEM REMOVAL/INSTALLATION .)
    2. Floor under cover (Refer to FLOOR UNDER COVER REMOVAL/INSTALLATION .)
    3. Brace bar (Refer to EXHAUST SYSTEM REMOVAL/INSTALLATION .)
  4. Disconnect the HO2S connector.
    Fig 1: Disconnecting HO2S Connector
    G10947145Courtesy of MAZDA MOTORS CORP.
  5. Remove the nut.
  6. Remove the clip A from the bracket.
  7. Remove the clip B from the body.
  8. Remove the HO2S using the SST  .
    Fig 2: Removing HO2S Using SST
    G10947146Courtesy of MAZDA MOTORS CORP.
  9. Install in the reverse order of removal.

AWD 

G10947147Courtesy of MAZDA MOTORS CORP.
  1. Disconnect the negative battery terminal. (Refer to NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION .)
  2. Lift up the vehicle.
  3. Remove the floor under cover (LH). (Refer to FLOOR UNDER COVER REMOVAL/INSTALLATION .)
  4. Disconnect the HO2S connector.
    Fig 3: Disconnecting HO2S Connector
    G10947148Courtesy of MAZDA MOTORS CORP.
  5. Remove the nut.
  6. Remove the clip A from the bracket.
  7. Remove the clip B from the body.
  8. Remove the HO2S using the SST  .
    Fig 4: Removing HO2S Using SST
    G10947149Courtesy of MAZDA MOTORS CORP.
  9. Install in the reverse order of removal.
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