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Powerbook 3400c Troubleshooting!
Posted by: lapalace on 2025-01-28 09:03:34 Hey hoping someone with experience troubleshooting these 3400cs might be able to help me here! Grabbed PowerBook 3400c for £20 in unknown condition and it's in pretty good condition. However, I haven't been able to get it to power up. The symptons are: a super barely audible high pitch and a crackle indicating some sort of power is getting to the board. I can get the power LED to go green if I hold PRAM reset key combo or hold the reset button on the back but it still gets no further. I have swapped out the DC power board with two others and the symptoms remain consistent. The only sign of damage I can see is corrosion at the back of the board near the DC jack but none on it. It seems to be affecting these three resistors: R48, R51, R53. But everything else seems fine, including caps. Could it just be these resistors?! Any help or insight would be appreciated! Thanks🙂
Posted by: DarthNvader on 2025-01-28 09:33:51 Delicately clean the corrosion and retest. Corrosion is never good.
Posted by: MacUp72 on 2025-01-28 10:52:29 old story, exactly over this whole area ( under the speaker panel) sits the green Varta PRAM battery of death, when it once leaked and electrolyte dripped onto the components beneath it, it is likely damaged/dead ( 47uF cap area)..I had two machines with little corrosion there, also did pay for a ultrasonic cleaning, but and it never booted again properly.
Posted by: lapalace on 2025-01-28 23:57:49 old story, exactly over this whole area ( under the speaker panel) sits the green Varta PRAM battery of death, when it once leaked and electrolyte dripped onto the components beneath it, it is likely damaged/dead ( 47uF cap area)..I had two machines with little corrosion there, also did pay for a ultrasonic cleaning, but and it never booted again properly. View attachment 82800 Hm, okay. PRAM battery was fine when I took it out, no sign of corrosion so not so sure why my machine is corroded where it is.
Posted by: MacUp72 on 2025-01-29 03:08:48 oh, mine didnt look bad either..maybe you can see some green corrosion that wicked through the cable/ connector..
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