Powerbook G3 PMU problem???

The machine will flash the green LED light, and the fan spins, but it will not boot.
nygacr95 wrote on :

I have a problem with my old wallstreet that I cannot seem to fix.

The computer is a G3 powerbook wallstreet 300MHZ, 20GB hard drive, and right now, 256 MB ram (yeah, I know real high tech...)

It seems to be centered around the PMU board, and the machine will not boot. The machine will flash the green LED light, and the fan spins, but it will not boot.

I was told this is a faulty PMU board, and after I swapped it, it was fine. for a while

Again, a couple of weeks ago, I replaced the PMU board for the same problem, and it went away, for a few useage cycle, and now I find it won't boot again, same scenario, fan spins, light comes on, but nothing.

I tried all of the PRAM resets, and nothing works.

I guess the question I got is, what's making the PMU boards go out? is there somehting that I have been overlooking? is there something else that is faulty that is contributing to the PMU board failure?

any help would be greatly appreciated!

Thanks! Rick

Blackjack Joe replied on :

In article d63fe399dba052ff0e7fc97d0b9f9104@redacted.invalid, "nygacr95" ckrantz3NoSpAm@redacted.invalid wrote:

I have a problem with my old wallstreet that I cannot seem to fix.

The computer is a G3 powerbook wallstreet 300MHZ, 20GB hard drive, and right now, 256 MB ram (yeah, I know real high tech...)

It seems to be centered around the PMU board, and the machine will not boot. The machine will flash the green LED light, and the fan spins, but it will not boot.

I was told this is a faulty PMU board, and after I swapped it, it was fine. for a while

Again, a couple of weeks ago, I replaced the PMU board for the same problem, and it went away, for a few useage cycle, and now I find it won't boot again, same scenario, fan spins, light comes on, but nothing.

I tried all of the PRAM resets, and nothing works.

I guess the question I got is, what's making the PMU boards go out? is there somehting that I have been overlooking? is there something else that is faulty that is contributing to the PMU board failure?

any help would be greatly appreciated!

Thanks! Rick

I just had the PMU replaced in a Wallstreet. Cost me $250 at AllMac in Santa CLara.

Fred McKenzie replied on :

In article d63fe399dba052ff0e7fc97d0b9f9104@redacted.invalid, "nygacr95" ckrantz3NoSpAm@redacted.invalid wrote:

The computer is a G3 powerbook wallstreet 300MHZ, 20GB hard drive, and right now, 256 MB ram (yeah, I know real high tech...)

It seems to be centered around the PMU board, and the machine will not boot. The machine will flash the green LED light, and the fan spins, but it will not boot.

I was told this is a faulty PMU board, and after I swapped it, it was fine. for a while

Again, a couple of weeks ago, I replaced the PMU board for the same problem, and it went away, for a few useage cycle, and now I find it won't boot again, same scenario, fan spins, light comes on, but nothing.

Rick-

Consider the possibility that you are replacing perfectly good PMU boards.

I had a bad PMU in my Wallstreet, but the symptom was that the battery appeared charged but would run down immediately. I assumed the battery was bad, bought a new one and a few days later had the same problem again. When the PMU was replaced, I had two good batteries.

What happens when you replace a PMU board? Do you remove the RAM to get to it? If there were an intermittent or dirty connection in the RAM socket, reseating it might have made it work for a while, until a few heating-cooling cycles caused it to malfunction again. The same might have been true for any other connectors that were disconnected in the process of the repair.

Fred