My QMX was also stuck in linear mode (PWM was at max, ADC_3V3 was less than 3v).? Thanks to W8GU for suggestion to check the inductor on the 3.3v supply.? I was able to measure a continuity issue, and then spot the broken wire, as per photo below:
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I was able to carefully scrape insulation from the broken wire and establish a connection to the board as per photo below:
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Unit now properly moves to SMPS mode, and Main Menu appears.
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Tim
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