I'm at a bit of a loss as to what is wrong with my mid-2012 15" MacBook Pro Retina (i7, 16GB RAM, Intel & Nvidia GPU). This will be a bit of an essay so bear with me! Background Bought in September 2012, had logic board and GPU replaced under Apple Repair scheme due to faulty graphics. Also had battery replaced in March 2018 for failure within healthy cycle count. I also bought a new MagSafe charger once the battery was replaced as mine was beginning to fray at the connection. Issue I was sitting using my MacBook for surfing the web, a bit of thesis writing with no issues. Battery was charging and the light on the charger was on and green. I switched it off, unplugged the charger from the Mac and mains and set it back into my office without plugging the mains back in (I would normally keep it on mains even when fully charged on advice from Apple). The next day, I plugged in the charger and found the amber/green light wasn't coming on and when I looked in the System Report, AC charge was not being detected and the battery was not charging (not an issue at the time as battery was 100%). I changed the socket being used and again, the charger light was not coming on and the System Report was showing no connected charger. The MacBook itself is still working perfectly despite this (no start up issues, no random shutdown, a little overheating but updates were occurring and the fans shut off once the process was complete). However, with the MacBook switched off and left on the charger for a few hours, the light comes on and the MacBook charges perfectly but one you use the MacBook on the AC charger for more than 5 minutes, the light of the charger switches off and the System Report no longer detects AC charge connected. I also reset the PRAM and SMC multiple times however this issue persisted. I took the MacBook into my local Apple the next day where I found out my model had been declared vintage only days before and they wouldn't repair it. At the Genius Bar, all they did was connect their own charger which again, wouldn't light up or be detected, tested my charger on one of their MacBooks (it works perfectly), then opened my MacBook to check the connections to the logic board and I/O board. As the connections were deemed to be ok, they said take to a repair shop. I then took the MacBook to an authorised service provider who opened it up and declared immediately a logic board failure, without any testing... he then said as the model was vintage, tracking a logic board would be difficult with a new one costing £700 before VAT and repair costs. As the MacBook is working perfectly besides not detecting AC charge while it is switched on, and needing to be left on charge for a few hours before its detected, I'm not convinced it's a logic board failure, and I'm beginning to suspect the MagSafe board itself. I've looked online to see if anyone else has had a similar problem to me and can't find anything as most also entail random shutdowns, other issues or the light on the charger fading/flickering whereas mine is bright and steady when it does come on. Has anyone here seen/been through/heard of something similar? I really don't want to pump loads of cash into this model if it is something minor to be repaired. I also really need to get my MacBook back in action ASAP as I'm completing my bioinformatics PhD and my MacBook Air just does not have the power necessary for programming. Any advice is massively appreciated!!