Replaced top case, now Mac not charging

Hi - thanks so much for your response! I replaced the top case because the left shift key was not working. I will open it back up tonite when I get off work and check the battery connector. Should I will try the Alt+CMD+P+R before doing that?

Sure, try it first. Nothing to loose. If it doesn't help, check the connector then repeat the reset then test.

If you do the reset correctly, laptop starts, chimes, then reboots. After it restarts, you can let go of the buttons. If you keep holding down, the laptop will keep resetting and restarting.

By the way, why did the left shift key stop working? Any particular cause? I hope it is not liquid damage.

So.... I got home last nite and pulled the battery back out, replaced it and thought I had it good. Then when I put the last screw in the back case (closest to the charging port) it stopped charging. Left that screw out and started charging. Left it plugged in and charged up to 98%. Now not charging again. When I connect the charger the charger light blinks on for a second and then goes out. Not charging. I did the Alt+CMD+P+R and it didn't help. Any thoughts? Also of interest in the middle of this my charger quit working completely - I had to get another one - what are the odds of that??? I know the one I am using now works fine b/c I have checked it on a friends MAC that I borrowed. PS I don't know why the left shift key quit working

If I were you I'd start by removing the board to check that nothing is out of place, causing a short between components on the board, or shorting components to ground. Specially check the screw hole where the screw is affecting the charging function. Don't use metal tools on the board except for the screw drivers & only on screws. For everything else gently use a nylon spudger / a plastic prying tool.

These kinds of shorts may affect the functioning of the charger, or it could be a coincidence that it quit at that precise moment. I'd try it with a different laptop to be sure. If you do, don't leave it plugged in for a long time in case it's defective. You don't want to fry another laptop.

I had laptops with a damaged charging circuit that acted similar to yours, but not exactly the same, so I can't generalise. I also had a laptop that wouldn't charge when I put it back together. Ended up being a short because of improper reassembly. Symptoms match with yours except that the charger did not quit on me.