G3 B&W won't always start up?

[kfdan]

Any electrical genius on the board?  I seem to be having an electrical or power supply problem.  How can I find out if the problem is from the power transformer in the computer or electrical connections to the main hard drive?

[reader50]

Need more data. Have you tried a different hard drive? Or tried booting from an install CD?

While the power supply (that's the proper name for the transformer-in-the-computer) could be failing, it's more likely the original hard drive is pooping out. And very likely the PRAM battery (on the motherboard, somewhere near the door hinge) has gone dead. A dead PRAM battery will cause erratic booting. Electrical connections are generally not high on my suspect list.

PRAM battery: Lithium 3.7V, size: 1/2 AA, fairly cheap on eBay.

[FdB]

Yes kfdan please, more information would be very useful. Such as processor speed, any expansion cards added and present, machine used frequently, dust blown out of it lately, AND even more specific sequential… details/symptom descriptions on just exactly what it does… or how it does, or does not boot?

Might be as simple as a new battery or even removing RAM and then re-seating it. Or again, any number of other possibly very simple reasons and/or fixes.

Is your B&W G3 a Rev.1 or Rev.2 series logic board?

[Petros90]

I had this issue 15 years ago with my G3 B&W Rev2, so I put it in storage.

Booted it up a few weeks ago (for the first time since 2003).

I was told by my local IT centre that it could be the power supply.

I thought I'd try it before taking it to them, and found the ON button is a really tight fit in the case - this was the problem.

A gentle press is all that's required, it now boots every time.

Strange, but true. I now have the equivalent of a three-year-old G3.

Try it

[Petros90]

BTW the battery was totally dead (15 years old) and the G3 booted every time over a two week period, had to keep resetting the date

[macStuff]

the B+W g3 is the freakiest of all the g3/g4 machines
in that it can be unpredictable..
i think ive read that this is usually attributed to the fact that its the first "new world rom" machine and that the
openfirmware implementation wasnt fully 100% all there yet

[DieHard]

I was told by my local IT centre that it could be the power supply.

I thought I'd try it before taking it to them, and found the ON button is a really tight fit in the case - this was the problem.

A gentle press is all that's required, it now boots every time.

Strange, but true. I now have the equivalent of a three-year-old G3.

Try it

That would be the rarest of exceptions. Usually, a G3 or G4 that appears to have a faulty "Power button" is almost always the Power supply.  Usually a "trickle power" issue.  After having literal dozens of clients come in over the years saying "it's just the power button, I know it's simple, I play with it and then it powers on" it is NEVER the button, on a Mac anyway (cheap PC power click switches go bad all the time)... as far as G3/G4 maybe 2 to 3 times in over 20 years.  Also, some areas that are humid create oxidation/corrosion issues, clean the button board with electronic cleaner.  Lastly, try the "hair dryer" trick (search for it here and on the web); if that works, then definitely the PS is going.  sometimes with a PS that is going, you will not see the issues again until you unplug it for a few days and then re-plug it is and try it; just cause it boots every time now with it plugged in, I am not convinced that the issue will not return

[kfdan]

Going to get a PRAM battery: Lithium 3.7V, size: 1/2 AA, for starters ... that could solve the issue.