AIR CONDITIONING SYSTEM, Diagnostic DTC:B14B8

DTC Code DTC Name
B14B8 Refrigerant Shortage

DESCRIPTION

This DTC is stored if the amount of refrigerant in the air conditioning system is insufficient.

The air conditioning amplifier assembly receives the ambient temperature signal, refrigerant pressure signal, etc. from various sensors.

Based on these signals, the air conditioning amplifier assembly detects the amount of refrigerant.

The A/C switch indicator is turned off and the air conditioning system is stopped if the amount of refrigerant is insufficient.

DTC No. Detection Item DTC Detection Condition Trouble Area Memory
B14B8 Refrigerant Shortage

When following condition is detected in refrigerant shortage check in normal operation:

Amount of refrigerant is insufficient

  • Refrigerant pipe line

  • Cooler expansion valve

  • Air conditioning amplifier assembly

Memorized

(15 min. or more)*1

CAUTION / NOTICE / HINT

Tech Tips

If DTC B1423/23 and B14B8 are output at the same time, troubleshoot for DTC B1423/23 first.

Click here

PROCEDURE


  1. CHECK FOR AIR CONDITIONING SYSTEM LEAK


    1. Install a manifold gauge set.

    2. Recover the refrigerant from the air conditioning system using a refrigerant recovery unit.

    3. Evacuate the air conditioning system and check that vacuum can be maintained in it.

      OK
      Vacuum can be maintained in the air conditioning system.

      Tech Tips

      If vacuum cannot be maintained in the air conditioning system, refrigerant may be leaking from it. In this case, it is necessary to repair or replace the leaking part of the air conditioning system.

      Result
      Proceed to
      OK
      NG

    NG

    REPAIR AIR CONDITIONING SYSTEM LEAK Click here

    OK

  2. CHARGE SYSTEM WITH REFRIGERANT


    1. Add an appropriate amount of refrigerant.

      for HFC-134a(R134a): Click here

      for HFO-1234yf(R1234yf): Click here

      Result
      Proceed to
      NEXT

    NEXT

  3. CHECK FOR DTC


    1. Check for DTCs when the following conditions are met.

      Click here


      Body Electrical > Air Conditioner > Trouble Codes
      Measurement Condition
      Item Condition
      A/C switch On
      A/C operation time 15 minutes or more
      Ambient temperature* 0 to 49°C (32 to 120°F)
      Engine coolant temperature 45°C (113°F) or more

      • *: If the ambient temperature is not within the range shown, do not perform this check.

      Result
      Result Proceed to
      DTC B14B8 is output A
      DTC B14B8 is not output B

    B

    END

    A

  4. REPLACE COOLER EXPANSION VALVE


    1. Replace the cooler expansion valve with a new or known good one.

      Click here

      Tech Tips

      Replace the cooler expansion valve with a new or known good one because the cooler expansion valve is either stuck or clogged.

      Result
      Proceed to
      NEXT

    NEXT

  5. CHARGE SYSTEM WITH REFRIGERANT


    1. Add an appropriate amount of refrigerant.

      for HFC-134a(R134a): Click here

      for HFO-1234yf(R1234yf): Click here

      Result
      Proceed to
      NEXT

    NEXT

  6. CHECK FOR DTC


    1. Check for DTCs when the following conditions are met.

      Click here


      Body Electrical > Air Conditioner > Trouble Codes
      Measurement Condition
      Item Condition
      A/C switch On
      A/C operation time 15 minutes or more
      Ambient temperature* 0 to 49°C (32 to 120°F)
      Engine coolant temperature 45°C (113°F) or more

      • *: If the ambient temperature is not within the range shown, do not perform this check.

      Result
      Result Proceed to
      DTC B14B8 is output A
      DTC B14B8 is not output B

    A

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here

    B

    END

  7. REPAIR AIR CONDITIONING SYSTEM LEAK


    1. Identify the area where refrigerant leaks.

      for HFC-134a(R134a): Click here

      for HFO-1234yf(R1234yf): Click here

    2. Repair the identified area of the air conditioning system.

    3. Evacuate the air conditioning system.

      Result
      Proceed to
      NEXT

    NEXT

  8. CHARGE SYSTEM WITH REFRIGERANT


    1. Add an appropriate amount of refrigerant.

      for HFC-134a(R134a): Click here

      for HFO-1234yf(R1234yf): Click here

      Result
      Proceed to
      NEXT

    NEXT

  9. CHECK FOR DTC


    1. Check for DTCs when the following conditions are met.

      Click here


      Body Electrical > Air Conditioner > Trouble Codes
      Measurement Condition
      Item Condition
      A/C switch On
      A/C operation time 15 minutes or more
      Ambient temperature* 0 to 49°C (32 to 120°F)
      Engine coolant temperature 45°C (113°F) or more

      • *: If the ambient temperature is not within the range shown, do not perform this check.

      Result
      Result Proceed to
      DTC B14B8 is output A
      DTC B14B8 is not output B

    B

    END

    A

  10. REPLACE COOLER EXPANSION VALVE


    1. Replace the cooler expansion valve with a new or known good one.

      Click here

      Tech Tips

      Replace the cooler expansion valve with a new or known good one because the cooler expansion valve is either stuck or clogged.

      Result
      Proceed to
      NEXT

    NEXT

  11. CHARGE SYSTEM WITH REFRIGERANT


    1. Add an appropriate amount of refrigerant.

      for HFC-134a(R134a): Click here

      for HFO-1234yf(R1234yf): Click here

      Result
      Proceed to
      NEXT

    NEXT

  12. CHECK FOR DTC


    1. Check for DTCs when the following conditions are met.

      Click here


      Body Electrical > Air Conditioner > Trouble Codes
      Measurement Condition
      Item Condition
      A/C switch On
      A/C operation time 15 minutes or more
      Ambient temperature* 0 to 49°C (32 to 120°F)
      Engine coolant temperature 45°C (113°F) or more

      • *: If the ambient temperature is not within the range shown, do not perform this check.

      Result
      Result Proceed to
      DTC B14B8 is output A
      DTC B14B8 is not output B

    A

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here

    B

    END