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

  • Refrigerant pipe line

  • Cooler expansion valve

  • Air conditioning amplifier assembly

Memorized

(15 minutes or more)

Tech Tips

The air conditioning amplifier assembly stores the DTC of the respective malfunction if it has occurred for the period of time indicated in the parentheses.

CAUTION / NOTICE / HINT

Note


  • This DTC is stored when there is no refrigerant in the system, when DTC B1423/23 and B14B8 are output simultaneously, perform troubleshooting for DTC B14B8 first.

  • Before disconnecting the cable from the negative (-) battery terminal or replacing the air conditioning amplifier assembly, record the last operation state of the air conditioning for each transmitter. After replacement, it is necessary to perform memory registration for each transmitter.

    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.


      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
      Engine condition Engine running

      Tech Tips


      • If the air conditioning amplifier assembly determines that the amount of refrigerant is insufficient, it may stop air conditioning system operation after 11 minutes elapse to avoid compressor burnout.

      • *: 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 (AMOUNT OF REFRIGERANT WAS DEFECTIVE)

    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.


      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
      Engine condition Engine running

      Tech Tips


      • If the air conditioning amplifier assembly determines that the amount of refrigerant is insufficient, it may stop air conditioning system operation after 11 minutes elapse to avoid compressor burnout.

      • *: 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 (COOLER EXPANSION VALVE WAS DEFECTIVE)

  7. REPAIR AIR CONDITIONING SYSTEM LEAK


    1. Identify the area where refrigerant leaks.


    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.


      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
      Engine condition Engine running

      Tech Tips


      • If the air conditioning amplifier assembly determines that the amount of refrigerant is insufficient, it may stop air conditioning system operation after 11 minutes elapse to avoid compressor burnout.

      • *: 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 (REFRIGERANT PIPE LINE WAS DEFECTIVE)

    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.


      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
      Engine condition Engine running

      Tech Tips


      • If the air conditioning amplifier assembly determines that the amount of refrigerant is insufficient, it may stop air conditioning system operation after 11 minutes elapse to avoid compressor burnout.

      • *: 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 (COOLER EXPANSION VALVE WAS DEFECTIVE)