System Diagnosis
Pipe sensor short/open
Troubleshooting guide for the Mitsubishi Electric Default system fault LED LD3 (Flash).
Sensor values that do not match the operating condition or drift when the harness is moved.
A control board issue can look like a failed sensor if the reference voltage or connector is unstable.
ACLogics has guided diagnostics for 73 Mitsubishi Electric fault codes and asks the right questions to narrow it down.