Sub-Zero System Messages

Meaning & Troubleshooting Guide

Power System Messages
PF
Power Failure Detected
  • Check household power supply and breaker.
  • Reset appliance by unplugging for 5–10 minutes.
  • Verify voltage stability.
  • Reconfigure settings after restart.
PO
Power On Reset
  • Normal startup message after power restoration.
  • Allow system to complete initialization.
  • Check temperature stabilisation.
  • No repair needed unless persistent.
Door & Safety Messages
dO
Door Open Warning
  • Ensure door is fully closed.
  • Check door gasket for damage or debris.
  • Inspect door switch alignment.
  • Close door to resume operation.
Control System Messages
CL
Control Lock Active
  • Press and hold lock button for 3–5 seconds.
  • Check control panel responsiveness.
  • Clean keypad surface.
  • Reset power if lock persists.
Service & Maintenance
SH
Service Mode Active
  • Appliance is in diagnostic/service mode.
  • Exit service mode via control panel sequence.
  • Consult technician manual if needed.
  • Restart system after exit.
System Reset Messages
rS
Reset Required
  • Power cycle the appliance.
  • Wait 5–10 minutes before restart.
  • Check for recurring error codes.
  • Inspect control board if issue repeats.
Temperature Alarms
AL
High Temperature Alarm
  • Check door seal and ensure proper closure.
  • Inspect condenser airflow and cleanliness.
  • Verify compressor operation.
  • Allow unit to stabilize after reset.
Important: If system messages persist frequently, disconnect power and contact a certified Sub-Zero technician.