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DTC P0137

DTC P0137  : Secondary HO2S (Sensor 2) Circuit Low Voltage

NOTE: Before you troubleshoot, review the general troubleshooting information .
DTC Description Confirmed DTC Pending DTC
P0137 Secondary HO2S (Sensor 2) Circuit Low Voltage    

DTC (PGM-FI)

  1. Problem verification

    -1. Turn the vehicle to the ON mode.

    -2. Clear the DTC with the HDS.

    -3. Turn the vehicle to the OFF (LOCK) mode.

    -4. Enter the maintenance mode, then start the engine .

    -5. Hold the engine speed at 3000 RPM without load (in P or N) until the radiator fan comes on, then let it idle.

    -6. Monitor the OBD STATUS for DTC P0137 in the DTCs MENU with the HDS.

    DTC Description OBD STATUS
    P0137 Secondary HO2S (Sensor 2) Circuit Low Voltage  

    OBD Status

    Does the HDS indicate FAILED?

    YES 

    The failure is duplicated. Go to step 2.

    NO 

    If the HDS indicates PASSED, 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 on-board snapshot of this DTC is recorded, try to reproduce the failure under the same conditions with the on-board snapshot . If the HDS indicates EXECUTING, keep idling until a result comes on. If the HDS indicates OUT OF CONDITION, go to step 1-5 and recheck.

  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. Turn the vehicle to the ON mode.

    -4. Check the parameter(s) below with the HDS.

    Signal Threshold Current conditions
    Values Unit Values Unit
    HO2S S2 Less than 0.15 V    

    Data List

    Do the current condition(s) match the threshold?

    YES 

    Go to step 3.

    NO 

    Replace secondary HO2S (Sensor 2) .

  3. Determine possible failure area (short in SO2 line, short in SO2 SG line)

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

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

    Test condition Vehicle OFF (LOCK) mode
      Secondary HO2S (Sensor 2) 4P connector: disconnected
    Test point 1 Secondary HO2S (Sensor 2) 4P connector (male terminals) No. 1:
    Test point 2 Body ground
    GHH384872Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    Go to step 4.

    NO 

    Go to step 5.

  4. Shorted wire check (SO2 line)

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

    -2. Disconnect the following connector.

    PCM connector A (50P)

    -3. Check for continuity between test points 1 and 2.

    Test condition Vehicle OFF (LOCK) mode
      Secondary HO2S (Sensor 2) 4P connector: disconnected
      PCM connector A (50P): disconnected
    Test point 1 Secondary HO2S (Sensor 2) 4P connector (male terminals) No. 1:
    Test point 2 Body ground
    GHH384874Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    Repair a short in the SO2 wire between the PCM (A47) and secondary HO2S (Sensor 2).

    NO 

    The SO2 wire is OK. Check for any authorized service information related to the DTCs or symptoms you are troubleshooting, or substitute a known-good PCM , then recheck. If DTC P0137 goes away and the PCM was substituted, replace the original PCM .

  5. Shorted wire check (SO2 SG line)

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

    -2. Disconnect the following connector.

    PCM connector A (50P)

    -3. Check for continuity between test points 1 and 2.

    Test condition Vehicle OFF (LOCK) mode
      Secondary HO2S (Sensor 2) 4P connector: disconnected
      PCM connector A (50P): disconnected
    Test point 1 Secondary HO2S (Sensor 2) 4P connector (male terminals) No. 2:
    Test point 2 Body ground
    GHH384876Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    Repair a short in the SO2 SG wire between the PCM (A48) and secondary HO2S (Sensor 2).

    NO 

    The SO2 SG wire is OK. Check for any authorized service information related to the DTCs or symptoms you are troubleshooting, or substitute a known-good PCM , then recheck. If DTC P0137 goes away and the PCM was substituted, replace the original PCM .