Mitsubishi Electric PUHY-P72 Service Manual page 182

[ IX Troubleshooting ]
1. Error Code
4220
(THMU-A)
4225
Logic error (Detail code 111)
2. Error definition and error detection method
H/W error
If only the H/W error logic circuit operates, and no identifiable error is detected.
3. Cause, Check method and remedy
In the case of 4220
(1) External noise
(2) INV board failure
(3) IPM failure (P120 model only)
(4) DCCT failure (P120 model only)
In the case of 4225
(1) External noise
(2) Fan board failure
Refer to section -6- "Inverter (THMU-A)" under part [4] Troubleshooting Principal Parts for error codes related to the
inverter.(page 244)
HWE0804A
Cause
Cause
- 173 -
Check method and remedy
Refer to IX [4] -6- (2) [1].(page 246)
Replace the IPM.
Replace the DCCT.
Check method and remedy
Refer to IX [4] -6- (2) [6].(page 247)
GB