Dead but clicking Hanns-G HC194D?

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  • momaka
    master hoarder
    • May 2008
    • 12164
    • Bulgaria
    #21
    Re: Dead but clicking Hanns-G HC194D?

    Originally posted by Per Hansson
    You might be able to do that but it could cause more damage too.
    Better would be to lift the input leg of the 7812
    Then power it up and see what voltage you have on the input then.
    I agree.
    Just remove the 7812 regulator and see if the PSU can start up.
    To remove the 7812, first unscrew it from the heatsink. Then, using a sharp blade or flat screwdriver, separate it from the heatsink (otherwise it might be a little stuck due to thermal compound.) After this, put a blob of solder over its leads on the bottom and pull it out. Should come out fairly easily.

    Once the 7812 is out, plug in the PSU again. If the 12V rail is still reading low, try putting a load on the 5V rail (like a 12V PC fan or two or perhaps a car 12V incandescent light bulb rated for 1-3 Watts) to see if the 12V rail goes up.

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