Pismo Squealing Sound - Bad Power Board?

#1 Thu, 21 Apr 2011 - 17:05 68kMLA

One of my Pismos has developed a new tic - a little bit of "squealing" when the battery is low when replugged to power. This has happened now a couple of times and then goes away. The battery still recharges ok; it runs on power ok; the reset button in back does not seem to stop the squeal per se. Is this a sign that the power management board is about to poop out? Has anyone else experienced this? I'd rather track down a board and replace that than have it fry one of my batteries...

#2 Fri, 22 Apr 2011 - 00:04 68kMLA

Could be the inverter too - have a closer listen ...

#3 Fri, 29 Apr 2011 - 04:23 68kMLA

2 things cause this.

1, the caps could be starting to dry up, or the ferrite cores on PFC inductors are starting to work loose, and your hearing saturation switching noise.