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Tried good working power supply - no light on any diagnostics LEDs. Inspected board for corrosion or explosions - nothing. Seems like there are no schematics for this board either. Any known issues with this board? Any idea what it can be?
Checked voltage on pins 4,5,6, 10,11,12 - 0V
Checked for short - shorted
Replaced Q8450 (12V_S0) FET - no short
voltage on pins 4,5,6, 10,11,12 is 0.45V now.
Please advise.
No. First time I injected it at J6900. Now I tried to inject it directly at 12V_G3H and I got green light on the first diagnostics led.
I went poking around for more short and found another one on PP12V_S0 line. Tried to inject 12V there but it only takes 1V since its shorted to ground. Nothing heats up. Whats my next move? Thanks!
Discard first any shorted high-side MOSFET from a secondary power supply connected to 12V_S0.
Compare short value with ohm value to ground from correspondinf big coils.
If nothing strange, then start injecting with 1V and slowly go up.
Let ampers adjust at max on the lab power supply.