I'm trying to find out what element is the one that is on the PCB that is labeled as QD2. On the body it has mark W16 and 95, but I couldn't find anywhere on internet what this element is. This is from the dishwasher PCB. I believe it's not transistor.

Can anyone help? Thanks

SMDenter image description here enter image description here

  • \$\begingroup\$ What makes you believe it's not transistor? Belief shouldn't play a role. Have you traced out the surrounding schematic? \$\endgroup\$ – mike65535 Nov 26 '18 at 14:17
  • \$\begingroup\$ possibly a CMPZDA47V dual zener (if you don't believe it's a transistor) \$\endgroup\$ – isdi Nov 26 '18 at 14:34
  • \$\begingroup\$ Thank you both for reply. Well, there are other elements in the same housing with mark on top 6CW (and 94 beside) that have label Q on the board, while this one has QD, therefore I was assuming it's not transistor (or at least only a transistor). \$\endgroup\$ – Srecko Podvinski Nov 26 '18 at 14:39
  • \$\begingroup\$ In addition, PIN that is single on one side goes to a relay that turns on and off heat pump. \$\endgroup\$ – Srecko Podvinski Nov 26 '18 at 14:43
  • \$\begingroup\$ The other two pins goes to ground and IC - dma24mrelux \$\endgroup\$ – Srecko Podvinski Nov 26 '18 at 14:59

It's an NPN pre-biased 100mA/50V transistor with 10K series base and 10K shunt emitter-base resistors.

Nexperia PDTC114ET

enter image description here

P.S. The QD2 device appears to have suffered a traumatic death. Suggest checking the flyback diode as they sometimes fail short (especially the LL4148 variety), which of course will kill any replacement.

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  • \$\begingroup\$ Thank you very much Spehro. This looks very promising. Do you know what "95" stands for on the transistor? I found some "W16" on internet, but they have differend second number. I wonder what role it plays. Thanks again for your help! \$\endgroup\$ – Srecko Podvinski Nov 26 '18 at 19:33
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    \$\begingroup\$ 95 is probably the date code or similar thing with little meaning. \$\endgroup\$ – Spehro Pefhany Nov 26 '18 at 19:37
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    \$\begingroup\$ Hi Spehro. I would like to thank you once again for your tips. I didn't had chance till today and was also waiting for the transistor to arrive, but now I managed to replace it and after that it burned out again. Then I checked the flyback diode which was showing zeros in both direction. Luckily I had something on stock so I replaced it with 1n4148 though I'm not sure what the old one was. Anyway the relay that turns on the water heater now heats the water. Thanks again and happy new year! \$\endgroup\$ – Srecko Podvinski Jan 7 '19 at 9:36

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