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Macintosh Portable M5126 Reboot Loop
Posted by: MaCJaX on 2024-12-27 22:45:08 Greetings all! I just received a Macintosh Portable M5126 and did a complete recap on the logic board. I am able to get it to power on and I get a happy chime but it's stuck in a reboot loop, rebooting and chiming every 3 to 5 seconds. The board has been cleaned in a ultrasonic cleaner. I also triple checked all traces under/around caps and all tested good. I checked the reset pin (pin 10) on CPU and it goes and stays high. Any ideas on what to check? Thanks!!
Posted by: Byrd on 2024-12-28 17:25:51 Try powering it without mains power using a fully charged 12V battery (and 9V battery) - do you have more luck?
Posted by: MaCJaX on 2024-12-28 21:40:30 Try powering it without mains power using a fully charged 12V battery (and 9V battery) - do you have more luck? Thanks for the response. Yes, that's what I have been doing actually. I new, fully charged 6V and 9V battery only.
Posted by: Byrd on 2024-12-28 22:00:37 Oops sorry, I did mean 6V main battery! With what is a power issue, I'd be having a good look around the hybrid module, potentially even desolder it and clean underneath. You can get modern hybrid replacements here: Macintosh Portable Hybrid Module Recreation – Tech by Androda androda.work
Posted by: MaCJaX on 2024-12-30 11:27:04 Oops sorry, I did mean 6V main battery! With what is a power issue, I'd be having a good look around the hybrid module, potentially even desolder it and clean underneath. You can get modern hybrid replacements here: Macintosh Portable Hybrid Module Recreation – Tech by Androda androda.work Thanks but this is the M5126 backlit version that doesn't use that module.
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