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DTC P0138, P0158 (2016 2017)

DTC P0138  : Rear Secondary HO2S (Bank 1, Sensor 2) Circuit High Voltage

DTC P0158  : Front Secondary HO2S (Bank 2, Sensor 2) Circuit High Voltage

NOTE: 

DTC Description Confirmed DTC Pending DTC Freeze Frame
P0138 Rear Secondary HO2S (Bank 1, Sensor 2) Circuit High Voltage      
P0158 Front Secondary HO2S (Bank 2, Sensor 2) Circuit High Voltage      

DTC (PGM-FI)

  1. Problem verification

    -1. Turn the vehicle to the ON mode.

    - 2. Clear the DTC with the HDS.

    - 3. Start the engine.

    - 4. Hold the engine speed at 3, 000 rpm without load (in P or N) until the radiator fan comes on, then let it idle.

    Signal Current conditions
    Values Unit
    ECT SENSOR 1    
    Signal Current conditions
    Values Unit
    ENGINE SPEED    

    - 5. Check the parameter (s) below with the HDS.

    Signal Threshold Current conditions
    Values Unit Values Unit
    HO2S B1 S2 More than 1.27 V    
    HO2S B2 S2 * More than 1.27 V    

    Do the current condition (s) match the threshold?

    YES 

    The failure is duplicated. Go to step 2.

    NO 

    Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at secondary HO2S (Sensor 2) and the PCM. If the freeze data/on-board snapshot of this DTC is recorded, try to reproduce the failure under the same conditions with the freeze data/on-board snapshot - Refer to: How to Troubleshoot the Fuel and Emissions Systems

  2. Determine possible failure area (secondary HO2S (Sensor 2), others)

    -1. Turn the vehicle to the OFF (LOCK) mode.

    - 2. Disconnect the following connector.

    Secondary HO2S (Sensor 2) 4P connector

    - 3. Connect terminals A and B with a jumper wire.

    Terminal A Secondary HO2S (Sensor 2) 4P connector No. 1
    Terminal B Secondary HO2S (Sensor 2) 4P connector No. 2
    GHH307171Courtesy of HONDA, U.S.A., INC.
    GHH307172Courtesy of HONDA, U.S.A., INC.

    - 4. Turn the vehicle to the ON mode.

    - 5. Check the parameter (s) below with the HDS.

    Signal Threshold Current conditions
    Values Unit Values Unit
    HO2S B1 S2 More than 1.27 V    
    HO2SB2 S2 * More than 1.27 V    

    Do the current condition (s) match the threshold?

    YES 

    Go to step 3.

    NO 

    Replace secondary HO2S (Sensor 2) .

  3. Open wire check (SO2SGB1 (SO2SGB2) * line):

    - 1.Turn the vehicle to the OFF (LOCK) mode.

    - 2. Remove the jumper wire from the secondary HO2S (Sensor 2) 4P connector.

    - 3. Connect terminals A and B with a jumper wire.

    Rear bank (Bank 1): 

    Terminal A Rear secondary HO2S (Bank 1, Sensor 2) 4P connector No. 2
    Terminal B Body ground

    Front bank (Bank 2): 

    Terminal A Front secondary HO2S (Bank 2, Sensor 2) 4P connector No. 1
    Terminal B Body ground
    GHH307173Courtesy of HONDA, U.S.A., INC.
    GHH307174Courtesy of HONDA, U.S.A., INC.

    - 4. Turn the vehicle to the ON mode.

    - 5. Check the parameter (s) below with the HDS.

    Signal Threshold Current conditions
    Values Unit Values Unit
    HO2S B1 S2 More than 1.27 V    
    HO2S B2 S2 * More than 1.27 V    

    Do the current condition (s) match the threshold?

    YES 

    The SO2SGB1 (SO2SGB2) * wire is OK. Go to step 4.

    NO 

    Repair an open in the SO2SGB1 (SO2SGB2) * wire between the PCM (C39 (C40) *) and secondary HO2S (Sensor 2).

  4. Open wire check (SO2B1 (SO2B2) * line):

    - 1.Turn the vehicle to the OFF (LOCK) mode.

    - 2. Jump the SCS line with the HDS, and wait more than 1 minute.

    - 3. Disconnect the following connector.

    PCM connector C (51P)

    - 4. Check for continuity between test points 1 and 2.

    Test condition Vehicle OFF (LOCK) mode
     
     
     
     
    Rear secondary HO2S (Bank 1, Sensor 2) 4P connector: disconnected
    Rear secondary HO2S (Bank 1, Sensor 2) 4P connector No. 2: jumped to body ground
    Front secondary HO2S (Bank 2, Sensor 2) 4P connector: disconnected *
    Front secondary HO2S (Bank 2, Sensor 2) 4P connector No. 1: jumped to body ground *
      PCM connector C (51P): disconnected
    Test point 1
     
    PCM connector C (51P) No. 30 - Refer to:
    PCM Connector for Inputs and Outputs (9-Speed A/T) (2016 2017 2018),
    PCM Connector for Inputs and Outputs (6-Speed A/T) (2016 2017 2018 2019 2020)
    PCM connector C (51P) No. 31 * - Refer to:
    PCM Connector for Inputs and Outputs (6-Speed A/T) (2016 2017 2018 2019 2020), or
    PCM Connector for Inputs and Outputs (9-Speed A/T) (2016 2017 2018)
    Test point 2 Body ground

    Is there continuity?

    YES 

    The SO2B1 (SO2B2) * wire is OK. Check for any authorized service information related to the DTCs or symptoms you are troubleshooting or substitute a known-good PCM - Refer to: PCM Removal and Installation (6-Speed A/T), (9-Speed A/T 2016 2017 2018) .

    NO 

    Repair an open in the SO2B1 (SO2B2) * wire between the PCM (C30 (C31) *) and secondary HO2S (Sensor 2).