P1 - The indoor unit intake sensor is reporting an error.
Mitsubishi Electric's PEAD installation manual lists P1 as an intake sensor error. In practice, this points to a fault with the return-air temperature sensing circuit rather than a normal user setting issue.
Applies to the PEAD-M50-140JAA installation-manual family; confirm exact controller behavior against the installed model.
Severity
High
Display
Shown as check code P1 on the wired remote controller. On supported self-check patterns, the wireless remote table maps one beep/flash count to P1.
Support first?
Often not
Models in range
PEAD-M50JAA(D), PEAD-M60JAA(D), PEAD-M71JAA(D)
What to do first
Start with these checks
- 1Turn the system off and restart it once after a short wait to see whether the code clears.
- 2Check that the return-air path is not blocked and that filters are seated correctly before restarting.
- 3If the code returns, stop using the system and book service.
Likely causes
What usually sits behind this code
Faulty indoor intake thermistor
Loose, damaged, or disconnected sensor wiring
Indoor control-board sensing fault
Contact support
Contact customer support if any of these apply
- !P1 returns immediately after restart
- !Cooling or heating is lost together with the code
- !The system repeatedly trips into fault after short run times
- - The official table labels P1 specifically as 'Intake sensor error'.
- - The manual's check-code table is for PEAD-M50-140JAA indoor units.
More ranges
More Mitsubishi Electric air-conditioner ranges
Source notes
Source and scope
Source: Mitsubishi Electric Australia installation manual
The PEAD-M50-140JAA installation manual lists P1 in the check-code table as 'Intake sensor error'.
Last reviewed: 2026-04-19
Meanings are taken from Mitsubishi Electric official documentation. Exact diagnosis still requires a qualified technician because the code table does not identify the failed part with component-level certainty.