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DTC P0136

DTC P0136  : Secondary HO2S (Sensor 2) Circuit Malfunction

NOTE:  Before you troubleshoot, review the general troubleshooting information .

DTC Description Confirmed DTC Pending DTC
P0136 Secondary HO2S (Sensor 2) Circuit Malfunction    

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 neutral) until the radiator fan comes on, then let it idle.

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

    Signal Threshold Current conditions
    Values Unit Values Unit
    HO2S S2 Less than 2.80 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 on-board snapshot of this DTC is recorded, try to reproduce the failure under the same conditions with the on-board snapshot .

  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 (female terminals) No. 1:
    Terminal B Secondary HO2S (Sensor 2) 4P connector (female terminals) No. 2:
    GHH404197Courtesy 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 S2 More than 2.80 V    

    Do the current condition (s) match the threshold?

    YES 

    Go to step 3.

    NO 

    Replace secondary HO2S (Sensor 2) .

  3. Open wire check (SO2SG 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.

    Terminal A Secondary HO2S (Sensor 2) 4P connector (female terminals) No. 2:
    Terminal B Body ground
    GHH404199Courtesy 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 S2 More than 2.80 V    

    Do the current condition (s) match the threshold?

    YES 

    The SO2SG wire is OK. Go to step 4.

    NO 

    Repair an open in the SO2SG wire between PCM connector No. 1 terminal No. 24 and secondary HO2S (Sensor 2).

  4. Open wire check (SO2 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 No. 1 (96P)

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

    Test condition Vehicle OFF (LOCK) mode
      Secondary HO2S (Sensor 2) 4P connector: disconnected
      Secondary HO2S (Sensor 2) 4P connector No. 2: jumped to body ground
      PCM connector No. 1 (96P): disconnected
    Test point 1 PCM connector No. 1 (96P) No. 22
    Test point 2 Body ground

    Is there continuity?

    YES 

    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 P0136 goes away and the PCM was substituted, replace the original PCM .

    NO 

    Repair an open in the SO2 wire between PCM connector No. 1 terminal No. 22 and secondary HO2S (Sensor 2).