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DTC P0840

DTC P0840  : Transmission Fluid Pressure Sensor Malfunction

NOTE: Before you troubleshoot, review the General Troubleshooting Information .
DTC Description Confirmed DTC Pending DTC Freeze Frame
P0840 Transmission Fluid Pressure Sensor Malfunction      

DTC (Gear)

  1. DTC check

    -1. Turn the vehicle to the ON mode.

    -2. Clear the DTC with the HDS.

    -3. Enter the maintenance mode , then start the engine until the cooling fan comes on.

    -4. Turn the vehicle to the OFF (LOCK) mode.

    -5. Turn the vehicle to the ON mode.

    -6. Raise the vehicle on a lift. Make sure it is securely supported, and allow all four wheels to rotate freely.

    -7. Select the ENERGY FLOW screen on the MID.

    -8. Enter the VSA maintenance mode .

    -9. Run the vehicle in the engine drive mode for at least 10 seconds. Apply the brakes, and slowly bring the wheels to a stop.

    Do not brake hard when working on a running vehicle on a lift. It may cause some damage to the drive-line.

    -10. Check for Pending or Confirmed DTCs with the HDS.

    DTC Description Confirmed DTC Pending DTC Freeze Frame
    P0840 Transmission Fluid Pressure Sensor Malfunction      
    P173A Transmission Fluid Pressure Sensor Performance High      
    P173B Transmission Fluid Pressure Sensor Performance Low      

    Is DTC P0840, P173A, or P173B indicated?

    DTC P0840 is indicated

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

    DTC P173A is indicated

    Do the troubleshooting for DTC P173A .

    DTC P173B is indicated

    Do the troubleshooting for DTC P173B .