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DTC P0405

DTC P0405  : EGR Valve Position Sensor Circuit Low Voltage

NOTE: Before you troubleshoot, review the general troubleshooting information .
DTC Description Confirmed DTC Pending DTC
P0405 EGR Valve Position Sensor Circuit Low Voltage    

DTC (PGM-FI)

  1. Problem verification

    -1. Turn the vehicle to the ON mode.

    -2. Check the parameter(s) below with the HDS.

    Signal Threshold Current conditions
    Values Unit Values Unit
    EGR Valve Position Sensor (EGR Vls) 0.35 or less V    

    Data List

    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 the EGR valve 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 (VCC2 line)

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

    -2. Disconnect the following connector.

    EGR valve 5P connector

    -3. Turn the vehicle to the ON mode.

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

    Test condition Vehicle ON mode
    EGR valve 5P connector: disconnected
    Test point 1 EGR valve 5P connector (female terminals) No. 2:
    Test point 2 EGR valve 5P connector (female terminals) No. 3:
    GHH385038Courtesy of HONDA, U.S.A., INC.

    Is there about 5.0 V?

    YES 

    The VCC2 wire is OK. Go to step 3.

    NO 

    Repair an open in the VCC2 wire between the PCM (E77) and the EGR valve.

  3. Shorted wire check (EGRL 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 E (80P)

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

    Test condition Vehicle OFF (LOCK) mode
      EGR valve 5P connector: disconnected
      PCM connector E (80P): disconnected
    Test point 1 EGR valve 5P connector (female terminals) No. 4:
    Test point 2 Body ground
    GHH385040Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    Repair a short in the EGRL wire between the PCM (E69) and the EGR valve.

    NO 

    The EGRL wire is not shorted. Go to step 4.

  4. Open wire check (EGRL line)

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

    Test condition Vehicle OFF (LOCK) mode
      EGR valve 5P connector: disconnected
      PCM connector E (80P): disconnected
    Test point 1 EGR valve 5P connector (female terminals) No. 4:
    Test point 2 PCM connector E (80P) No. 69
    GHH385042Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    The EGRL wire is OK. Go to step 5.

    NO 

    Repair an open in the EGRL wire between the PCM (E69) and the EGR valve.

  5. PCM internal circuit check

    -1. Connect terminals A and B with a jumper wire.

    Terminal A EGR valve 5P connector (female terminals) No. 2:
    Terminal B EGR valve 5P connector (female terminals) No. 4:
    GHH385045Courtesy of HONDA, U.S.A., INC.

    -2. Reconnect PCM connector E (80P).

    -3. Exit the SCS mode with the HDS.

    -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
    EGR Valve Position Sensor (EGR Vls) 0.35 or less V    

    Data List

    Do the current condition(s) match the threshold?

    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 P0405 goes away and the PCM was substituted, replace the original PCM .

    NO 

    The PCM internal circuit is OK. Replace the EGR valve .