There isn’t battery leakage, could be caps I’m suspecting tooCould be capacitors, could be battery leakage. These old 68k laptops often need capacitors replaced, with the leakage causing potentially a lot of random issues.
It doesn’t works, sometimes the light will turn off. Press power, lights on but nothing happens. Sometimes the light turn on and blink once every few secondstry unplugging it while holding the power button, then plug it back in and attempt to power it on.
... is there a reason why it was shelved NOS for 20 years? Might explain the GLOD (green light of death), a common issue with many PowerBook Duos and usually not related to caps. Check also the output of your PSU and any SMT fuses near the DC jack.
will a faulty display prevent it from powering up?as others have said it is most likely caps, I would suggest replacing the ones near the DC jack first and verifling that the problem is solved before tearing the display assembly open and attempting to recap
you are right, this is a spare part board and it still leaked. Look at the leak.Yes indeed, the capacitors will leak whether they were actually powered up or not. So NOS parts, still sealed, never used, stored properly... can still come right out of the bag with capacitors leaking and corroded traces on the board. Sigh.
Based on the melted plastic around the base of the "new caps" in the photo above I'd say it might not be a job to tackle without a little more practice.You should also recap the display! This is a tricky job. I'd follow the Apple take apart procedures to remove the top cover of the display. I use a small needle to get under the screw covers and gently move around to get the plastic covers off the front. Be careful not to bend or stick the needle in the delicate plastic covers. I then rub all the old sticky glue of and use scotch double sided thin tape cut to size. Once you start unscrewing with a T8 I think it is, the screw mounts will fall apart. I use JB Weld 2 part epoxy and rebuild an entirely new mount with the metal screw anchor in the middle. It's a very tedious job but in the end you get really strong mounts. Once the cover is off the top you can access the display and remove the plastic white covering over the display and get to the caps.. There are like 10 small caps.. I replace with all Tantalum. Also you have to remove the inverter board and replace one capacitor on that. Typically these caps don't leak so this is an option if you want to do this! If your not confident enough I would NOT perform this recap job. I've done tons of them. If you have a spare machine maybe test your skills on another one.