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I have 6.5v going into the board molex from the bench supply. After "resetting" PMGR On the PMGR P57 2.74v (A/D_FILTER), P57(PMGR_PWM) 0v Back at the Hybrid P62 (A/D) 2.74v P39(HICHG) 0v P25(BATTSENSE) 6.49v P19(CHRG_ON) 5.15v P41 6.43v P8 2.99v P11 5.20v

Until I can get a PMGR chip to test, maybe it's a good idea to post the current sit rep and see if something jumps out at somebody So, applying 6.5V to the on board molex (both +ve and -ve connected), no extra peripherals, just speaker and keybd. No sound from speaker and initial current draw...

Well here’s the before pic of the PMGR and VIA and they don’t look obviously eroded by capacitor venom. Pulled both and cleaned up the pads, no eaten tracks under the chips so I fear I have reached a temporary hiatus until I can try another PMGR. Oh well,  Color Classic time...  

I think as it's a Git project, if you notice anything amiss, report it back so it can be corrected and we all win as a village :-)

In my wading through Google search results, I came across this GitHub project to map out the schematics for the Hybrid board, and a project that will go into KiCad. It might help someone and I figured you can never have too much information... https://github.com/ppieczul/macintosh-portable

Thank you sir,  I also tried removing the SWIM and starting up, no change. I may pull the PMGR and see if anything amiss underneath from the nearby caps. If any philanthropist souls out there have a donor PMGR from a wrecked board, or a wrecked board, please make themselves known. It’s such a...

Hmm well maybe need to retitle two steps forward three back. Not getting a start up chime now. Same power as before from the bench supply direct to the molex on the board (both positives and nagatives). When I power on, I see a small amount of current draw down which gradually becomes zero or...

I got the first of these which I think is a Ram test failure for onboard bank b, but still chasing that one. 

Thanks for the enlightenment, will get the flashlight out again. Is there any tip for spotting via that are corroded away to the point they aren’t connected at all or just visual check. I assume the Portable is only dual layer pcb ?

Yes, I watched your video and made sure to do that, thanks! When you say "back row" you mean closest to the IO ports ? Still can't find anything that points out Bank A and B on the onboard Portable RAM.... I'm going to give it a bath first and then start looking for trace or through hole...

Powering the board through the molex connector from a bench lab supply. 6.5v with and a 1.5A current limit. When it powers up it draws about 400mA because none of the peripherals are attached. And yes both positive and negative connections are being fed. If I made a mistake with the recapping...

This is bare board, all cards and devices disconnected apart from speaker and keyboard...tried reset power manager and this is the same code each time. Which is good I guess... in another post I saw someone mentioned that they did something with the NMI but didn’t elaborate?

Non backlit Portable was dead to the world and in need of a recap. Someone wasn't kidding about the nasty fish smell - I thought thai fish sauce was pungent until the hot air cooked up  a whiff of funky bouillabaisse . But the recap operation seems to be *mostly* successful as I now power up...

Hi All I've watched a number of YouTube Portable Rescue videos and seen a couple of people shorting pins on the keyboard connector to start/wake it up when the board is on the bench. I could just reattach the keyboard but I'd like to join the Cool Kids Gang - I can never see which pins get...