Mitsubishi Electric Mini-Split 2 Blinks
Soft lockoutShown as: Upper OPERATION INDICATOR lamp blinks 2 times, then 2.5 seconds off, repeating
Indoor coil thermistor or room temperature thermistor error. One of the indoor temperature sensors reads short circuit or open circuit, so the unit cannot measure room or coil temperature.
Manual wording: “Indoor coil thermistor / Room temperature thermistor - The indoor coil or the room temperature thermistor is short or open circuit.”
Documented for: MSZ-GL and MSY-GL indoor units
Likely causes, most common first
- Indoor coil thermistor or room temperature thermistor out of its resistance range (defective)
- Thermistor connector loose or not fully seated on the indoor control board
- Broken or pinched thermistor lead wire
What you can safely check yourself
- Turn the system off at the breaker, wait one minute, and turn it back on once to see if the code clears
When to call a technician
Testing and replacing the indoor thermistors requires opening the indoor unit and measuring resistance at the control board. Have a technician do it.
A Mitsubishi Electric mini-split throwing this code repeatedly has a reason — clearing the code without fixing the cause just hides it.
Source
- Indoor Unit Service Manual No. OBH732 Revised Edition-D - MSZ-GL/MSY-GL Series (Mitsubishi Electric, MSZ-GL06NA/GL09NA/GL12NA/GL15NA/GL18NA/GL24NA and MSY-GL09NA/GL12NA/GL15NA/GL18NA/GL24NA wall-mounted indoor units) · checked 2026-08-25