Multimeter diode mode question

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  • darkness77
    Member
    • Dec 2019
    • 10
    • Craotia
    #1

    Multimeter diode mode question

    Hi, i am noob in repairing electronics and motherboards...and most of the time i am still trying to understand how things work...So, lately i have been using and testing motherboards in diode mode. Most of the motherboards that i test are not working and broken. The question is that if i use multimeter in diode mode on high 19vol rails sometimes i read fixed number in multimeter but on some other boards reading in diode mode is rising indefinitely till i read 1. I am talking on lets say ac_bat 19volt rails on motherboards. So, i dont understand how it is rising indefinitely? In theory if only capacitors are on that rail it should be ok...but there are more things then only capacitors.
    Should all the rails have fixed reading on diode mode or? I have seen some schematics with test points and they all have fixed number in diode mode!
    If not, if it is rising indefinitely like in my example what does it mean? Something wrong?
    Thx
    Tags: None
    • Fred_47
      New Member
      • Jul 2022
      • 2
      • USA
      #2
      Re: Multimeter diode mode question

      The rising voltage probably means that you're charging a capacitor.

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