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Does anyone know the resistance reading of the main primary winding of the smps(srt) across pins 6 and 9? I am getting 13Ω and there is no output at +B. I think the resistance is too high? I thought it should be ≤ 1Ω. See image...
I do not think the resistance is the problem. 13 ohms sounds fine for a primary winding with lots of turns. Either you have lost VBB to pin6 or the transistor on pin9 is not conducting.
My guess is that either the switcher cannot startup or has detected a fault and shut down. This is assuming that VBB is present and the transistor on pin9 is OK.
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