FC CONTROL SYSTEM, Diagnostic DTC:P1DEC-450, P1DED-450

DTC Code DTC Name
P1DEC-450 Hydrogen Tank No.2 Temperature Sensor Circuit Low
P1DED-450 Hydrogen Tank No.2 Temperature Sensor Circuit High

DESCRIPTION

The hydrogen tank temperature sensor is provided inside the tank valve sub-assembly of the No. 2 hydrogen tank assembly, and is used to detect hydrogen temperatures in the tank.

The resistance of the built-in thermistor of the hydrogen tank temperature sensor varies in accordance with variations in the tank internal hydrogen temperature. The lower the hydrogen temperature in the tank is, the greater the thermistor resistance becomes. On the contrary, the higher the temperature is, the smaller the resistance becomes.

Hydrogen temperatures in the tank are transmitted to the hydrogen fuel control ECU, and such information is used for corrections of the remaining amount of hydrogen as well as for the temperature control of the tank.

DTC No. Detection Item DTC Detection Condition Trouble Area Warning Indicate
P1DEC-450 Hydrogen Tank No.2 Temperature Sensor Circuit Low

Hydrogen Tank 2 Temperature Sensor Voltage remains at less than 0.1 V for more than 3 seconds.

(1 trip detection logic)

  • No. 2 hydrogen tank assembly (hydrogen tank temperature sensor 2)

  • Hydrogen fuel control ECU assembly

  • Wire harness or connector

 Master Warning Light: Comes on
P1DED-450 Hydrogen Tank No.2 Temperature Sensor Circuit High

Hydrogen Tank 2 Temperature Sensor Voltage remains at more than 4.9 V for more than 3 seconds.

(1 trip detection logic)

  • No. 2 hydrogen tank assembly (hydrogen tank temperature sensor 2)

  • 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
P1DEC-450 Hydrogen Tank 2 Temperature Sensor Voltage
P1DED-450

WIRING DIAGRAM

A01MI6JE02

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. READ VALUE USING GTS (HYDROGEN TANK 2 TEMPERATURE SENSOR VOLTAGE)


    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 / Data List / Hydrogen Tank 2 Temperature Sensor Voltage


      Powertrain > FC > Data List
      Tester Display
      Hydrogen Tank 2 Temperature Sensor Voltage

    5. Read the value displayed on the GTS.

      Result
      Hydrogen Tank 2 Temperature Sensor Voltage Proceed to
      Higher than 4.9 V A
      Less than 0.1 V B

      Tech Tips


      • If there is an open circuit, the GTS indicates higher than 4.9 V.

      • If there is a short circuit, the GTS indicates less than 0.1 V.


    B

    READ VALUE USING GTS (CHECK FOR SHORT IN WIRE HARNESS) Click here

    A

  2. READ VALUE USING GTS (CHECK FOR OPEN IN WIRE HARNESS)


    1. A01MIKD

      Disconnect the No. 2 hydrogen tank assembly (hydrogen tank temperature sensor 2) connector.

    2. A01MJOCC02
      *1 No. 2 Hydrogen Tank Assembly (Hydrogen Tank Temperature Sensor 2)
      *2 Hydrogen fuel control ECU assembly
      *a

      Front view of wire harness connector

      (to No. 2 Hydrogen Tank Assembly (Hydrogen Tank Temperature Sensor 2))

      Connect terminals 1 (TNT2) and 3 (GTT2) of the No. 2 hydrogen tank assembly (hydrogen tank temperature sensor 2) connector on the wire harness side.

    3. Connect the GTS to the DLC3.

    4. Turn the power switch on (IG).

    5. Turn the GTS on.

    6. Enter the following menus: Powertrain / FC / Data List / Hydrogen Tank 2 Temperature Sensor Voltage


      Powertrain > FC > Data List
      Tester Display
      Hydrogen Tank 2 Temperature Sensor Voltage

    7. Read the value displayed on the GTS.

      Standard value
      Less than 0.1 V (Short circuit)

    8. Turn the power switch off.

    9. Reconnect the No. 2 hydrogen tank assembly (hydrogen tank temperature sensor 2) connector.

      Result
      Proceed to
      OK
      NG

    OK

    REPLACE NO. 2 HYDROGEN TANK ASSEMBLY (HYDROGEN TANK TEMPERATURE SENSOR 2) Click here

    NG

  3. CHECK HARNESS AND CONNECTOR (HYDROGEN FUEL CONTROL ECU ASSEMBLY - NO. 2 HYDROGEN TANK ASSEMBLY (HYDROGEN TANK TEMPERATURE SENSOR 2))


    1. Disconnect the hydrogen fuel control ECU assembly connector.

    2. Disconnect the No. 2 hydrogen tank assembly (hydrogen tank temperature sensor) connector.

    3. A01MIA0C05
      *a

      Front view of wire harness connector

      (to No. 2 Hydrogen Tank Assembly (Hydrogen Tank Temperature Sensor))
      *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
      P30-30 (TNT2) - R3-1 (TNT2) Always Below 1 Ω
      P30-29 (GTT2) - R3-3 (GTT2) Always Below 1 Ω

    4. Reconnect the No. 2 hydrogen tank assembly (hydrogen tank temperature sensor) 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

  4. READ VALUE USING GTS (CHECK FOR SHORT IN WIRE HARNESS)


    1. A01MIKD

      Disconnect the R3 No. 2 hydrogen tank assembly (hydrogen tank temperature sensor 2) connector.

    2. Connect the GTS to the DLC3.

    3. Turn the power switch on (IG).

    4. Turn the GTS on.

    5. A01MHH9C06
      *1 No. 2 Hydrogen Tank Assembly (Hydrogen Tank Temperature Sensor 2)
      *2 Hydrogen Fuel Control ECU Assembly

      Enter the following menus: Powertrain / FC / Data List / Hydrogen Tank 2 Temperature Sensor Voltage


      Powertrain > FC > Data List
      Tester Display
      Hydrogen Tank 2 Temperature Sensor Voltage

    6. Read the value displayed on the GTS.

      Standard value
      Higher than 4.9 V (Open circuit)

    7. Turn the power switch off.

    8. Reconnect the R3 No. 2 hydrogen tank assembly (hydrogen tank temperature sensor 2) connector.

      Result
      Proceed to
      OK
      NG

    OK

    REPLACE NO. 2 HYDROGEN TANK ASSEMBLY (HYDROGEN TANK TEMPERATURE SENSOR 2) Click here

    NG

  5. CHECK HARNESS AND CONNECTOR (HYDROGEN FUEL CONTROL ECU ASSEMBLY - NO. 2 HYDROGEN TANK ASSEMBLY (HYDROGEN TANK TEMPERATURE SENSOR 2))


    1. Disconnect the hydrogen fuel control ECU assembly connector.

    2. Disconnect the No. 2 hydrogen tank assembly (hydrogen tank temperature sensor) connector.

    3. A01MIA0C06
      *a

      Front view of wire harness connector

      (to No. 2 Hydrogen Tank Assembly (Hydrogen Tank Temperature Sensor))
      *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
      P30-30 (TNT2) or R3-1 (TNT2) - Body ground and other terminals Always 10 kΩ or higher

    4. Reconnect the No. 2 hydrogen tank assembly (hydrogen tank temperature sensor) 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