FC CONTROL SYSTEM, Diagnostic DTC:P1DFC-450, P1DFD-450

DTC Code DTC Name
P1DFC-450 Hydrogen Filling System High Pressure Sensor Circuit Low
P1DFD-450 Hydrogen Filling System High Pressure Sensor Circuit High

DESCRIPTION

The hydrogen tank pressure sensor (for inlet side) is provided on the hydrogen tank tube joint (for inlet side), and is used to detect pressures in the No. 1 and No. 2 hydrogen tank assemblies and convert them into voltage.

The hydrogen fuel control ECU monitors hydrogen pressure when the tanks are filled.

A01MHZXE03
DTC No. Detection Item DTC Detection Condition Trouble Area Warning Indicate
P1DFC-450 Hydrogen Filling System High Pressure Sensor Circuit Low

Hydrogen Filling System High Pressure Sensor Voltage remains at less than 0.55 V for more than 3 seconds.

(1 trip detection logic)

  • Hydrogen tank pressure sensor (for inlet side)

  • Hydrogen fuel control ECU assembly

  • Wire harness or connector

 Master Warning Light: Comes on
P1DFD-450 Hydrogen Filling System High Pressure Sensor Circuit High

Hydrogen Filling System High Pressure Sensor Voltage remains at more than 4.95 V for more than 3 seconds.

(1 trip detection logic)

  • Hydrogen tank pressure sensor (for inlet side)

  • Hydrogen fuel control ECU assembly

  • Wire harness or connector

 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 ○ ○ ○ ○ ○ ○
Related Data List
DTC No. Data List
P1DFC-450 Hydrogen Filling System High Pressure Sensor Voltage
P1DFD-450

The following items can be helpful when performing repairs:


Tech Tips

If DTCs are found, read the "Hydrogen Filling System High Pressure Sensor Voltage" in the Data List on a GTS.

Hydrogen Filling System High Pressure Sensor Voltage Malfunction
Less than 0.55 V

  • Open in VHPC (5 V power supply) circuit

  • Short in HPC circuit to ground

  • Short in HPC circuit to GHPC (GND) circuit
Higher than 4.95 V

  • Short in VHPC circuit to HPC circuit

  • Open in HPC circuit

  • Open in GHPC (GND) circuit

Tech Tips

It is suspected that malfunctions, or open/short circuits have occurred in the Hydrogen tank pressure sensor (for inlet side).

WIRING DIAGRAM

A01MK2QE05

CAUTION / NOTICE / HINT

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. Turn the power switch on (IG) and wait for 1 minute or more.

PROCEDURE


  1. CHECK TERMINAL VOLTAGE (POWER SOURCE OF HYDROGEN TANK PRESSURE SENSOR (FOR INLET SIDE))


    1. A01MH7D

      Disconnect the hydrogen tank pressure sensor (for inlet side) connector.

    2. Turn the power switch on (IG).

    3. A0026HFC03
      *a

      Front view of wire harness connector

      (to Hydrogen Tank Pressure Sensor (for Inlet Side))

      Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Condition Specified Condition
      R4-3 (VHPC) - R4-1 (GHPC) Power switch on (IG) 4.75 to 5.25 V
      R4-2 (HPC) - R4-1 (GHPC) Power switch on (IG) 4.935 to 5.065 V

    4. Turn the power switch off.

    5. Reconnect the hydrogen tank pressure sensor (for inlet side) connector.

      Result
      Proceed to
      OK
      NG

    NG

    CHECK HARNESS AND CONNECTOR (HYDROGEN FUEL CONTROL ECU ASSEMBLY - HYDROGEN TANK PRESSURE SENSOR (FOR INLET SIDE)) Click here

    OK

  2. REPLACE HYDROGEN TANK PRESSURE SENSOR (FOR INLET SIDE)

    Click here

    Result
    Proceed to
    NEXT

    NEXT

  3. 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

  4. CHECK DTC OUTPUT


    1. Connect the GTS to the DLC3.

    2. Turn the power switch on (IG) and wait for 1 minute or more.

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

    4. Check for DTCs.


      Powertrain > FC > Trouble Codes
      Result
      Result Proceed to
      DTC P1DFC-450 or P1DFD-450 are output A
      DTCs are not output B

    5. Turn the power switch off.


    A

    REPLACE HYDROGEN FUEL CONTROL ECU ASSEMBLY Click here

    B

    END

  5. CHECK HARNESS AND CONNECTOR (HYDROGEN FUEL CONTROL ECU ASSEMBLY - HYDROGEN TANK PRESSURE SENSOR (FOR INLET SIDE))


    1. Disconnect the hydrogen fuel control ECU assembly connector.

    2. Disconnect the hydrogen tank pressure sensor (for inlet side) connector.

    3. A01MG5DC01
      *a

      Front view of wire harness connector

      (to Hydrogen Tank Pressure Sensor (for Inlet Side))
      *b

      Front view of wire harness connector

      (to Hydrogen Fuel Control ECU Assembly)

      Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      P30-32 (HPC) - R4-2 (HPC) Always Below 1 Ω
      P30-11 (GHPC) - R4-1 (GHPC) Always Below 1 Ω
      P30-12 (VHPC) - R4-3 (VHPC) Always Below 1 Ω
      P30-32 (HPC) or R4-2 (HPC) - Body ground and other terminals Always 10 kΩ or higher
      P30-12 (VHPC) or R4-3 (VHPC) - Body ground and other terminals Always 10 kΩ or higher

    4. Reconnect the hydrogen tank pressure sensor (for inlet side) connector.

    5. Reconnect the hydrogen fuel control ECU assembly connector.

      Result
      Proceed to
      OK
      NG

    OK

    REPLACE HYDROGEN FUEL CONTROL ECU ASSEMBLY Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR