Mitsubishi Electric HP120TNU-A Service Handbook page 172

[7-3 Error Code Definitions and Solutions: Codes [1000 - 1999] ]
7-3-2 Error Code [1301]
1. Error code definition
Low pressure fault
2. Error definition and error detection method
When starting the compressor from Stop Mode for the first time if low pressure reads 0.098MPa [14psi] immediately before
start-up, the operation immediately stops.
3. Cause, check method and remedy
Cause
(1) Inner pressure drop due to a leakage.
(2) Low pressure sensor failure
(3) Short-circuited pressure sensor cable due to
torn outer rubber
(4) A pin on the male connector is missing.
(5) Disconnected wire
(6) Failure of the low pressure input circuit on the
controller board
HWE18220_GB
Check method and remedy
Refer to the following page(s). [8-5-3 Comparing the Low-
Pressure Sensor Measurement and Gauge Pressure]
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