FC CONTROL SYSTEM, Diagnostic DTC:P1E48-450

DTC Code DTC Name
P1E48-450 Barometric Pressure Sensor / FC Stack Air Pressure Sensor (FC Stack Inlet) Correlation

DESCRIPTION

The air system of the FC system feeds the FC stack with oxygen, so that the FC stack can generate power. Based on the output from the FC stack inlet air pressure sensor (turbo pressure sensor), air pressure that is needed for FC stack power generation is regulated via the air pressure regulating valve and air shunt valve. However, the atmosphere pressure sensor is used to correct influence over air supply control at high altitudes.

When the pressure sensor value is compared to another pressure sensor value that is supposed to be equal to the said sensor value under specified conditions, if the value is significantly different from another sensor value, it will be interpreted as occurrence of abnormal sensor deviation, and this DTC will be set.

A01MIMLC01
*1 Mass Air Flow Meter *2 FC Air Compressor with Motor Assembly
*3 FC Air Compressor *4 Intercooler
*5 FC Gas Temperature Sensor *6 FC Stack Inlet Air Pressure Sensor (Turbo Pressure Sensor)
*7 Air Shunt Valve *8 FC Stack
*9 FC Stack Assembly *10 Air Pressure Regulating Valve
*11 FC Exhaust Tail Pipe Assembly *12 FC Control ECU
*13 Atmosphere Pressure Sensor - -
DTC No. Detection Item DTC Detection Condition Trouble Area Warning Indicate
P1E48-450 Barometric Pressure Sensor / FC Stack Air Pressure Sensor (FC Stack Inlet) Correlation

Malfunction detection is performed when the following condition is met with the power switch on (IG).

Difference between the outputs of the atmosphere pressure sensor (built into the FC control ECU) and the FC stack inlet air pressure sensor (turbo pressure sensor) has exceeded a threshold.

(3 times)

  • FC stack inlet air pressure sensor (turbo pressure sensor)

  • FC control ECU (atmosphere pressure sensor)

 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

The vehicle behavior when the FC stack inlet air pressure sensor (turbo pressure sensor) is malfunctioning is different from that when the FC control ECU (atmosphere pressure sensor) is malfunctioning.

Click here

Related Data List
DTC No. Data List
P1E48-450

  • Smoothed Value of FC Stack Air Pressure (FC Stack Inlet)

  • Smoothed Value of Barometric Pressure

Tech Tips

After the FC system is activated, the value of "Smoothed Value of FC Stack Air Pressure (FC Stack Inlet)" varies depending on the driving conditions.

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 5 seconds.

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.

    Tech Tips

    If DTC P1D6F-450 is set in the hybrid control system (EV) in addition to this DTC, it is suspected that the atmosphere pressure sensor (FC control ECU) is malfunctioning.


    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

    6. Turn the power switch off.

      Result
      Proceed to
      NEXT

    NEXT

  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. READ VALUE USING GTS (SMOOTHED VALUE OF FC STACK AIR PRESSURE (FC STACK INLET), SMOOTHED VALUE OF BAROMETRIC PRESSURE)


    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 / Smoothed Value of FC Stack Air Pressure (FC Stack Inlet), Smoothed Value of Barometric Pressure


      Powertrain > FC > Data List
      Tester Display
      Smoothed Value of Barometric Pressure
      Smoothed Value of FC Stack Air Pressure (FC Stack Inlet)

    5. Using the table, read the normal atmospheric pressure value for the applicable altitude.

      A01MH69

      Tech Tips


      • Standard atmospheric pressure is approximately 101 kPa (15 psi).

      • For every 100 m (328 ft.) increase in altitude, atmospheric pressure drops by approximately 1 kPa (0.1 psi). This varies by weather.

    6. Compare the "Smoothed Value of FC Stack Air Pressure (FC Stack Inlet)" and "Smoothed Value of Barometric Pressure" values in the Data List with the normal atmospheric value from the table.

      Note

      If the Data List values do not reproduce the symptom, check the values in the freeze frame data. Locate a malfunctioning area from the correlation between the 2 pressure sensor values.

      Result
      Result Proceed to
      Difference between "Smoothed Value of FC Stack Air Pressure (FC Stack Inlet)" in Data List and normal atmospheric pressure value is 10 kPa or more. A
      Difference between "Smoothed Value of Barometric Pressure" in Data List and normal atmospheric pressure value is 10 kPa or more. B
      Other than above. C

    7. Turn the power switch off.


    A

    REPLACE FC STACK INLET AIR PRESSURE SENSOR (TURBO PRESSURE SENSOR) Click here

    B

    REPLACE FC CONTROL ECU (ATMOSPHERE PRESSURE SENSOR) Click here

    C

    CHECK FOR INTERMITTENT PROBLEMS Click here