I think this will be a double diode so if it has three legs
do the following test on one side and the middle then do it on the other pair ( middle and other side)
Diodes (D or ZD designation) can be bad. To test a diode in circuit,
a) put your multimeter in diode test mode
b) put your black lead on one side and the red lead on the other - record reading
c) reverse the leads - recording reading
A good diode should read 0.4V to 0.7V in one direction and 0L in the other. If you get a reading in both directions
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Greetings,
Count me too in the success stories list: last week the display died (completely: no blue/orange led).
Found D22 died in closed circuit state, today I replaced it with a STPS60170CT and now it's back working flawlessly. It costed me about 3€ and 2 hours of work.
Thank you all for this great thread.
Greetings,
Count me too in the success stories list: last week the display died (completely: no blue/orange led).
Found D22 died in closed circuit state, today I replaced it with a STPS60170CT and now it's back working flawlessly. It costed me about 3€ and 2 hours of work.
Thank you all for this great thread.
Excellent! Great to hear! Now if we can get fuus fixed up; I'll be able to sleep again
Last edited by Lumberjack777; 08-15-2012, 11:29 PM.
Reason: mispelled name
SO:
Original D22 Readings:
Black Left, Red Centre: 007, Black Left, Red Right: 007
Red Left, Black Centre: 007, Red Left, Black Right: 007
Replaced D22 Readings:
Black Left, Red Centre: 1, Black Left, Red Right: 1
Red Left, Black Centre: 122, Red Left, Black Right: 1
Original D19 Readings: (potentially shorted one)
Black Left, Red Centre: 1, Black Left, Red Right: 1
Red Left, Black Centre: 052, Red Left, Black Right: 1
I applaud your commitment to helping people Lumberjack, I'm sure many people are grateful for the help!
When you check semiconductor device for short, use Ohm function since bad semiconductor junction will act more like low Ohm resistor, it will no longer act like Diode any more.
D22 is OK.
Check D19 in Ohm mode to see what you get, so far it looks like it has very low Vf.
I just want to thank the major contributors to this thread - I'm in the same predicament and have got quite a lot to go on thanks to the posts here. Have ordered a pack of STPS60170CTs (minimum order of 5 :/) and will hopefully be taking a look at it this weekend. It's quite promising how many people have fixed the issue by changing this single component.
"on the 200 setting I got a reading of 69.9 for red left and black centre
I also got 69.9 for black centre red right!"
Now do the reverse:
black left and red center
black right and red center
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