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DTC P0134

DTC P0134  : A/F Sensor (Sensor 1) Heater System Malfunction

NOTE:
DTC Description Confirmed DTC Pending DTC
P0134 A/F Sensor (Sensor 1) Heater System 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 without load (in P or N) for at least 1 minute.

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

    DTC Description Confirmed DTC Pending DTC
    P0134 A/F Sensor (Sensor 1) Heater System Malfunction    

    DTC (PGM-FI)

    Is DTC P0134 indicated?

    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 the A/F sensor (Sensor 1) 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. Open wire check (VS 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 connectors.

    A/F sensor (Sensor 1) 6P connector
    PCM connector E (80P)

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

    Test condition Vehicle OFF (LOCK) mode
      PCM connector E (80P): disconnected
      A/F sensor (Sensor 1) 6P connector: disconnected
    Test point 1 A/F sensor (Sensor 1) 6P connector (female terminals) No. 6:
    Test point 2 PCM connector E (80P) No. 73
    GHH384857Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    Go to step 3.

    NO 

    Repair an open in the VS wire between the PCM (E73) and the A/F sensor (Sensor 1).

  3. PCM internal circuit check

    -1. Reconnect the following connector.

    PCM connector E (80P)

    -2. Exit the SCS mode with the HDS.

    -3. Enter the maintenance mode, then start the engine , and let it idle without load (in P or N) for at least 1 minute.

    -4. Measure the voltage between test point 1 and 2.

    Test condition Engine running
      A/F sensor (Sensor 1) 6P connector: disconnected
    Test point 1 A/F sensor (Sensor 1) 6P connector (female terminals) No. 6:
    Test point 2 Body ground
    GHH384859Courtesy of HONDA, U.S.A., INC.

    Is there about 0.2 V or less?

    YES 

    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 P0134 goes away and the PCM was substituted, replace the original PCM .

    NO 

    Replace the A/F sensor (Sensor 1) .