MacBook Pro won't enter clamshell mode

[soohawaiian]

Just so you know this is my first post. I'm hoping someone might have any suggestions for an issue with my Mac. It won't enter clamshell mode anymore and when I close the lid it won't go to sleep itself unless I either wait awhile or usually manually do it. Sometimes the charger isn't recognized right away or requires jiggling before it lights up. Up until last month I had no problems with any of this happening. Let me know if there's anything else I should have included. Any ideas??

Specs
MacBook Pro 13" Mid-2012 Unibody
2.5 GHz Intel Core i5
8 GB 1600 MHz DDR3 (G.Skill 2x4GB)
750 GB Hard Drive (WD Blue)
OS X El Capitan 10.11.4

Modifications
I replaced the original 500 GB hard drive with the 750 GB WD about a year ago. Subsequently it appeared to be failing last month. Since it was under warranty still I got a replacement and installed it a 1-2 weeks ago. Around the same time last year I upgraded the original 2x2GB ram to 8GB total. In January my battery was going bad and I replaced it, but the new one was defective. Ordered another that was no good. Ended up getting a new one from iFixit, which I put in the last couple days. New top half since casing was scratched while in for diagnostics last week.

What I've already tried:

• Restart
• Shut Down overnight
• Reset SMC
• Reset PRAM
• Scanned for any Malware and Adware
• Diagnostic Test
• Checked Activity Monitor for anything preventing sleep
• Booted into Safe Mode
• Tried a different charger, but that doesn't seem to be the issue
• Tried the external monitor adapter with another computer and it worked
• Restored Defaults in Energy Saver
• Restored to Factory Settings
• Tried clamshell mode with another external monitor with no success
• Checked Displays settings
• Run DriveDx self-test

Apple
I brought it into Apple Genius Bar and extended diagnostics were performed on it. I was required to put all the original parts back in before they'd run more tests. If you ask me that's stupid since my original hard drive and battery were failing thus the replacements. They couldn't find any issues after having it for a week except what I already knew was failing. Prior diagnostic tests done while new parts were in didn't show any issues. Basically they didn't do anything except replace my screen after they scratched the outer case during service.

 

[snaky69]

This may be a stupid question, but I'll ask it anyway.

Is anything else plugged into the computer except the charger when trying to use clamshell? What about when it won't sleep? Mine will wake right back up from sleep when my external display is connected, I've yet to figure out why.

 

[soohawaiian]

This may be a stupid question, but I'll ask it anyway.

Is anything else plugged into the computer except the charger when trying to use clamshell? What about when it won't sleep? Mine will wake right back up from sleep when my external display is connected, I've yet to figure out why.

Sometimes I'll have a mouse plugged and/or a keyboard or my external monitor. Doesn't seem to matter what is or isn't. Mine does wake up if when it's closed I connect another display too.