FC CONTROL SYSTEM, Diagnostic DTC:P1DC3-450

DTC Code DTC Name
P1DC3-450 Medium-range Hydrogen Pressure Too High

DESCRIPTION

The hydrogen system of the FC system feeds the FC stack with hydrogen, so that the FC stack can generate power. In the hydrogen system, from the hydrogen supply regulator assembly (high-pressure regulator) to the hydrogen injectors are a group of components in the medium-range hydrogen pressure circuit.

The hydrogen supply regulator assembly mechanically depressurizes the tank original pressure that varies according to consumption, in order to regulate it to a specified medium-range pressure. If the medium-range hydrogen pressure has exceeded a threshold, the FC control ECU interprets that there is something wrong with the medium-range pressure components, and sets this DTC.

A01MHJGC03
*1 Hydrogen Inlet Receptacle Assembly *2 Hydrogen Tank Pressure Sensor (for Inlet Side)
*3 No. 1 Hydrogen Tank Assembly *4 No. 2 Hydrogen Tank Assembly
*5 Hydrogen Tank Temperature Sensor 1 *6 Hydrogen Tank Temperature Sensor 2
*7 Tank Shut Valve 1 *8 Tank Shut Valve 2
*9 Hydrogen Tank Pressure Sensor (for Outlet Side) *10 Hydrogen Supply Regulator Assembly
*11 Medium-range Hydrogen Pressure Sensor *12 Hydrogen Injector
*13 Low-range Hydrogen Pressure Sensor *14 FC Stack
*15 FC Stack Assembly *16 Exhaust Drainage Valve
*17 Hydrogen Pump *18 Air Shunt Valve
*19 Air Pressure Regulating Valve *20 Manual Valve
*21 Pressure Relief Valve *22 Pressure Relief Device
*a Hydrogen System *b Air System
*c From the FC Air Compressor with Motor Assembly *d To the exhaust drainage pipe
*e Medium-range Hydrogen Pressure Circuit - -
DTC No. Detection Item DTC Detection Condition Trouble Area Warning Indicate
P1DC3-450 Medium-range Hydrogen Pressure Too High

Medium-range hydrogen pressure has exceeded a threshold. This malfunction detection is active while the power switch is on (READY)(modes other than FC shutdown).

(1 trip detection logic)

  • Hydrogen supply regulator assembly

  • FC stack assembly (medium-range hydrogen pressure sensor)

  • Medium-range Hydrogen Pressure Pipe

 Master Warning Light: Comes on
Detection timing
Vehicle Condition

FC shutdown

(power switch on (IG))

 FC startup process FC intermittent operation

FC is generating power

(vehicle is in stationary)

FC is generating power

(vehicle is traveling)

 FC shutdown process

Data List

"FC Mode"

 FC Shutdown FC Startup Process FC Working FC Shutdown Process

Data List

"FC Intermittent Operation"

 OFF ON OFF OFF
DTC Detection - ○ ○ ○ ○ ○

Tech Tips

By accessing the "FC Mode" and "FC Intermittent Operation" in the freeze frame data, the FC system condition at the time the malfunction occurred can be checked.

Related Data List
DTC No. Data List
P1DC3-450 Smoothed Value of Medium-range Hydrogen Pressure

The following items can be helpful when performing repairs:



CAUTION / NOTICE / HINT

CAUTION:


  • Work procedures must be performed in an area with good ventilation (airflow) where hydrogen gas will not accumulate, and flames or other things that could act as ignition sources must not be present.

  • Accumulated hydrogen gas could ignite, resulting in a serious accident.

    Click here

B006JCR

Note

When the vehicle is parked with the power switch off, if the FC control ECU judges that the FC stack temperature will go below 0°C (32°F), it activates the FC air compressor, hydrogen pump and FC cooling water pump for a maximum of 180 seconds and drains water from the FC stack assembly. When performing inspection or repairs with the power switch off (not on (IG) or on (READY)), disconnect the cable from the negative (-) auxiliary battery terminal before performing work (If the auxiliary battery voltage is needed to conduct inspection, warm up the FC system beforehand).

Tech Tips

After the repair, clear the DTCs and perform the following procedure to check that DTCs are not output.


  1. Put the shift lever into P and turn the power switch on (READY), and then wait for at least 2 minutes with the FC Mode of the Data List in modes other than "FC Shutdown".

  2. Check that no hydrogen leaks from the hydrogen system components with a hydrogen gas detector.

PROCEDURE


  1. CHECK DTC OUTPUT

    Note

    The freeze frame data is cleared when DTCs are cleared. Be sure to make a note of necessary data in advance.


    1. Connect the GTS to the DLC3.

    2. Turn the power switch on (IG).

    3. Turn the GTS on.

    4. Enter the following menus: Powertrain / FC / Trouble Codes.

    5. Check for DTCs.


      Powertrain > FC > Trouble Codes
      Result
      Result Proceed to
      P1DC3-450 only is output, or DTCs except the ones in the table below are also output. A
      Any of the following DTCs are also output. B
      Malfunction Content Relevant DTC
      Sensor and Actuator Circuit Malfunction P1DB7-450 Medium-range Hydrogen Pressure Sensor Circuit Low
      P1DB8-450 Medium-range Hydrogen Pressure Sensor Circuit High

      Tech Tips

      DTC P1DC3-450 may be set due to problems that cause the DTCs shown above to be output. If such happens, troubleshoot the suspected area(s) corresponding to the output DTC(s) in order starting with the listed DTCs shown in the table above.

    6. Turn the power switch off.


    B

    GO TO DTC CHART Click here

    A

  2. CLEAR DTC


    1. Connect the GTS to the DLC3.

    2. Turn the power switch on (IG).

    3. Turn the GTS on.

    4. Enter the following menus: Powertrain / FC / Trouble Codes.

    5. Clear the DTCs.


      Powertrain > FC > Clear DTCs

    6. Turn the power switch off and wait for 3 minutes or more.

      Result
      Proceed to
      NEXT

    NEXT

  3. REPLACE HYDROGEN SUPPLY REGULATOR ASSEMBLY

    Click here

    Result
    Proceed to
    NEXT

    NEXT

  4. READ VALUE USING GTS (SMOOTHED VALUE OF MEDIUM-RANGE HYDROGEN PRESSURE)


    1. Connect the GTS to the DLC3.

    2. Turn the power switch on (READY).

    3. Turn the GTS on.

    4. Enter the following menus: Powertrain / FC / Data List / Smoothed Value of Medium-range Hydrogen Pressure


      Powertrain > FC > Data List
      Tester Display
      Smoothed Value of Medium-range Hydrogen Pressure

    5. Read the value displayed on the GTS.

      Result
      Result Proceed to
      Except the following* A
      "Smoothed Value of Medium-range Hydrogen Pressure" in the Data List is less than 1600 kPa(abs) B

      • *: The medium-range hydrogen pressure sensor is malfunctioning

    6. Turn the power switch off.


    A

    REPLACE FC STACK ASSEMBLY Click here

    B

    END