Troubleshooting symptom:- Not powering up, standby LED lit. (Stuck in standby.)
Found 5V rail measures 7.5V (hope nothing damaged!) and 3.3V measures 1.2V, 2.6V measures 0.6V. Noticed the 2.6V comes off the 3.3V though a silicon diode (giving it a 0.6~0.7V drop.) So the problem is with the 3.3V rail. Other rails are OK.
Tested the cap in circuit, 1176uF 8ohm. So obviously failed, though not bulging.
Upon pulling it, it's completely open. It measures 266nF. Yes, nanofarads. ESR can't be measured by my meter.
So in 6 years it went from functional to open circuit, it's a "TL" brand btw. Never heard of them.
Found 5V rail measures 7.5V (hope nothing damaged!) and 3.3V measures 1.2V, 2.6V measures 0.6V. Noticed the 2.6V comes off the 3.3V though a silicon diode (giving it a 0.6~0.7V drop.) So the problem is with the 3.3V rail. Other rails are OK.
Tested the cap in circuit, 1176uF 8ohm. So obviously failed, though not bulging.
Upon pulling it, it's completely open. It measures 266nF. Yes, nanofarads. ESR can't be measured by my meter.
So in 6 years it went from functional to open circuit, it's a "TL" brand btw. Never heard of them.
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