Macintosh portable stopped turning on after using PB100 adapter

[d3jsp]

Sorry I noticed that I probably shouldn't be powering this before recapping and getting a working battery first. But knowing it's condition, the 9V battery is probably dead

Received a Macintosh portable and tried to power it up using a 3A PB 100 7.5v power adapter. It turned on at first but shows an error code of 0300140b. Unplugged the adapter and tried to power it on again after a few seconds and it returned a different error 03001400 and 03001500

Unplugged the power adapter but now it will not turn on at all and just hums when plugged in. There is a really loud hum when first plugged in but the screen will not turn on and disk will not spin anymore.
Tried resetting the PMU but it didn't help. Could the PB100 adapter have fried something?

 

[finkmac]

you already knew it was a bad idea and you still did it. tsk tsk.

the mac portable power circuit requires a working battery.

recap the board and source a replacement battery, THEN you can debug this issue.

 

[3lectr1cPPC]

I’d definitely agree that you shouldn’t test further until recapping. If you don’t care about running the machine off battery, you can buy a “battery eliminator” board here: https://androda.work/product/macintosh-portable-battery-eliminator/

As for using PowerBook adapters, here’s my current understanding of things:
The Portable MUST have a working battery or that eliminator installed to work. This is because all the voltage regulation is done on the battery side only - bad things happen if you run it on the power supply alone. The stock 1.5A supply doesn’t have enough juice to start it with no battery, but the PowerBook 2A supplies can. It will work for a short amount of time like this, but the voltage rails will be unstable - what eventually happens is that the 5.2V rail will spike too high, and then you’ll blow out a whole bunch of the chips on the board. This will happen on both the M5120 and M5126 portables, but the M5120 is more sensitive to it.
Now - you used the 3A PowerBook 165c/180c supply. That basically just compounds the issue unfortunately, as it sends in even more power (what a poor circuit design by the way - Apple was just asking for this to happen).
You CAN use the more powerful chargers IF you have a working battery, but I’d also recommend against this as it will charge the battery faster than what it’s designed for, which may damage it over time.
Now - unfortunately, that board may be toast now. I’d try recapping it, getting a 1.5A adapter, new battery, and new HYBRID if you have an M5120, and hoping for the best, but a whole bunch of chips on that logic board may be bad now.