Hitachi 50" rear projection. Dead!!

[Dani]

Model # 50UX57B, Chassis # AP83R, dead, was worked on elsewhere, both
convergence IC's were replaced, & E995, E996, as well as IK04, & IK05.
D910, & D9110 12 volt zener diodes shorted, C707 near the flyback, &
horizontal output are fine, the SMPS just won't oscillate! The three
opto couplers check ok, as well as the SMPS electrolytics! Ideas
anyone? Thanks, Dani.

 

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Model # 50UX57B, Chassis # AP83R, dead, was worked on elsewhere, both
convergence IC's were replaced, & E995, E996, as well as IK04, & IK05.
D910, & D9110 12 volt zener diodes shorted, C707 near the flyback, &
horizontal output are fine, the SMPS just won't oscillate! The three
opto couplers check ok, as well as the SMPS electrolytics! Ideas
anyone? Thanks, Dani.

How does the pulse look did you check peak to peak & freq