How to test a thyristor B422NC

[LA1]

this 3 terminal one has me baffled. between all the terminals on continuity test I get open loop(OL) On diode test I get between 1 and 3 i get 290 mV (.290) either way switching probes. Just noticed the part numbers are different, the part looks the same

[stj]

Re: How to test a thyristor B422NC

its a bi-directional zener diode basically,
the datasheet will tell you the trigger voltage

a thyristor is different.
similar to a transistor but only on/off nothing in between.

[LA1]

Re: How to test a thyristor B422NC

not sure anyway, that seems not what i am looking for. I have decided it's part of the onboard network card. I have a HP AIO 24-f0061, it's an i5. I got it for free , would like to repair it. it's getting a beep code for crowbar circuit failure. none of the fets are getting anything at their gates. the processor is getting warm though.
looking at the pwm chip RT3602AC

[stj]

Re: How to test a thyristor B422NC

crowbar?
i didnt know they used any!
well a shorted ceramic cap is most likely.
something dead short anyway.