VIN 36V when it’s actually 12V
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Can you measure the voltage across R81 too?
Are your thermistors reading correctly?
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@wennis said in VIN 36V when it’s actually 12V:
Voltage on R81 is 3.26V
That's much too high! Almost as if it's shorted to +3.3V or VREF.
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Oh I see... does it mean the resistor is faulty and I should replace it?
Do you know which replacement part I should get if that’s the case?
Thank you for your help!
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SMD resistors rarely fail. The only time I have seen one fail, under magnification I could see a crack in it.
I suggest you use your multimeter to check its resistance.
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R81 was around 60 ohms. Is that okay?
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looking here, R81 should be 4k7
https://github.com/T3P3/Duet/blob/master/Duet2/Duet2v1.04/Duet2_1.04b_Schematic.pdf -
I suspect a short or near-short between that ADC input and +3.3V. It could be caused by a blown pin in the microcontroller, or by a bit of metal swarf shorting two pins of the microcontroller together.
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Okay, that doesn’t sound good. Are we talking about the U3 chip or the ARM chip?
I tried to clean the connection on the U3 chip, but it made no difference.
I’ll just get right to it. Is my board a dead board?