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DTC P0141

DTC P0141  : Secondary HO2S (Sensor 2) Heater Circuit Malfunction

NOTE: Before you troubleshoot, review the general troubleshooting information .
DTC Description Confirmed DTC Pending DTC
P0141 Secondary HO2S (Sensor 2) Heater Circuit Malfunction    

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 , and let it idle.

    -5. Check for Pending or Confirmed DTCs with the HDS.

    DTC Description Confirmed DTC Pending DTC
    P0141 Secondary HO2S (Sensor 2) Heater Circuit Malfunction    

    DTC (PGM-FI)

    Is DTC P0141 indicated?

    YES 

    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. Fuse check

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

    -2. Check the No. C21 fuse .

    Is the fuse OK?

    YES 

    Go to step 3.

    NO 

    Repair a short in the IG1 ACG wire between the No. C21 fuse and secondary HO2S (Sensor 2). Also replace the No. C21 fuse.

  3. Secondary HO2S (Sensor 2) internal heater resistance check

    -1. Disconnect the following connector.

    Secondary HO2S (Sensor 2) 4P connector

    -2. At the sensor side, measure the resistance 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 (female terminals) No. 3 (sensor side):
    Test point 2 Secondary HO2S (Sensor 2) 4P connector (female terminals) No. 4 (sensor side):
    GHH384891Courtesy of HONDA, U.S.A., INC.

    Is there 4.2-6.6 Ω at room temperature?

    YES 

    Go to step 4.

    NO 

    Replace secondary HO2S (Sensor 2) .

  4. Secondary HO2S (Sensor 2) internal circuit check

    -1. At the sensor side, check for continuity between test point 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 (female terminals) No. 3 and No. 4 (sensor side):
    Test point 2 Body ground
    GHH384893Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    Replace secondary HO2S (Sensor 2) .

    NO 

    Go to step 5.

  5. Shorted wire check (SO2HT 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 PCM connector A (50P) No. 4
    Test point 2 Body ground

    Is there continuity?

    YES 

    Repair a short in the SO2HT wire between the PCM (A4) and secondary HO2S (Sensor 2).

    NO 

    The SO2HT wire is not shorted. Go to step 6.

  6. Open wire check (SO2HT line)

    -1. 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. 3:
    Test point 2 PCM connector A (50P) No. 4
    GHH384895Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    The SO2HT wire is OK. Go to step 7.

    NO 

    Repair an open in the SO2HT wire between the PCM (A4) and secondary HO2S (Sensor 2).

  7. Open wire check (IG1 ACG line)

    -1. Turn the vehicle to the ON mode.

    -2. Measure the voltage between test points 1 and 2.

    Test condition Vehicle ON 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. 4:
    Test point 2 Body ground
    GHH384897Courtesy of HONDA, U.S.A., INC.

    Is there battery voltage?

    YES 

    The IG1 ACG 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 P0141 goes away and the PCM was substituted, replace the original PCM .

    NO 

    Repair an open in the IG1 ACG wire between the No. C21 fuse and secondary HO2S (Sensor 2).