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Hello, usually, the power of the control pad comes from the roof unit. Please check the step down transformer or the power supply for the 12 v DC for the controller. It might be in the pc board on the roof unit. Can you give the complete model number please?
the control unit in roof is the problem, will need a call out technician to replace, i cant progress further without removing whole control unit and having it tested
ok. Good luck on the repair.
the fuse housing in the roof CRU control motherboard has burnt out. I have removed the whole CRU, will get a replacement one from spares place. all the wires simply clip back in place.
the question is, would the fuse/fuse holder burnt out in the CRU by itself, or does it mean something more substantial has overloaded and burnt out. Will simply replacing CRU likely fix the problem?
also just checking wiring convention: green/yellow is earth , black is active, brown is neutral?
Hello, If the fuse holder got loose, it could burn itself, but if there is a part that would overload it, it would burn as well. My suggestion is; before you replace the CRU, have the motor be checked first for grounding or shorted wire as well as the water pump. These two parts would be a source of shorted or overloaded part. Check as well the wires that goes to these parts, check for cracks and damaged that could cause grounding of the unit.
Your wire configuration is correct.
If it is just the fuse holder that burnt out, can you just replace the fuse holder rather than replacing the whole CRU? Which could be much more less expensive than the whole CRU.