Lg50 pc1d-psu board faulty.

[cornboats]

Lg50 pc1d

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I have trouble fault finding a fault on psu board YPSU-JO12B.

Changed shorted Q855 SD20N60 power fet

Symptom-fuse keeps blowing.



All other Power fets tested ok.

removed Relays RL101 & R102 & tested ok

removed C603 & c603 power capacitors and tested ok.

removed diode D601 and tested ok.

Last time I tested the thyristers TH01 blew up as well as flowing fuse.