BCM Code B448: Low Refrigerant Pressure

In the process of controlling compressor clutch, BCM monitors certain system inputs for low refrigerant charge indication. This code indicates a low refrigerant condition was detected. If B448 is detected, compressor clutch will disengage and remain disengaged until diagnostic code is cleared.

Test Number 1)  Checks current state of low pressure switch.

Test Number 2)  Checks circuits to low pressure switch.

Test Number 3)  Checks refrigerant system pressure.

Test Number 4)  Checks for restriction in refrigerant system.

Test Number 5)  Checks for intermittent short or open.

Fig 1: BCM Code B448 Circuit Diagram

Fig 2: BCM Code B448 Flow Chart