Chosen Solution

Everything was working perfectly until two weeks ago, I went to a event which was taking place in the open and I had to open my Macbook where it was dusty and sunny. My Mac was in my bag all the time, and so it’s also possible that it might have endured some movement. Now, around 5 days ago, I opened my Mac and all of a sudden I can’t move the trackpad and can’t type in my password because the keyboard doesn’t work. So, I didn’t use the Mac at the event any more. I came back from the event two days ago and tried resetting SMC which worked, but resetting NVRAM and PRAM didn’t work, same with boot options (pressing Shift for Safe mode etc.). Connecting an external keyboard worked, but resetting NVRAM using the external keyboard and booting into safe mode didn’t solve the issue. Can anyone tell me what the issue could be? Please let me know if I should give any other information. Edit: (4/3/2019)

Here is the CoconutBattery screenshot. Having said that, let me mention the following points:

  1. My original charger’s cable connector became loose (the part which connects to the macbook) and I had to hold it up for charging. Soon, it stopped working, signalling an issue in the cable. So, I bought a replacement charger by FUGEN instead of the original charger 1.5 years ago. This could have led to an issue in the battery, as you say.
  2. Around 1 month ago I started receiving a message to Service the battery (like this: https://goo.gl/images/urW2EY). It’s not showing now, though. My battery life has deteriorated considerably too, running 3-4 hours at max on full charge, and rapidly discharging even in normal use.

Unlike the older MacBook Pro’s this series trackpad cable runs on top of the batteries Vs under them. So it is less protected. The trackpad cable carries both the trackpad signals and the keyboards so I would first replace the cable to see what happens. Here’s the IFIXIT guide to review: MacBook Pro 13" Retina Display Early 2015 Trackpad Replacement. Follow Steps 1 thru 6, then jump down to Steps 17 thru 20. Here’s the part you’ll need: MacBook Pro 13" Retina Trackpad Flex Cable, Early 2015 - Apple P/N 923-00518 As to what damaged the cable you’ll need to first dust out your system to make sure there is no sand grit as the space between the bottom cover and the cable is quite tight so the grit could damage the cable. The other possibility is the battery pack has swelled pressing the cable even tighter to the bottom case. For now lets keep the bottom cover off and run this app to check the battery CoconutBattery post a screenshot of the full main screen so we can see whats up with the battery. Update (03/04/2019) It also sounds like your MagSafe connection on the system is in bad shape. Here’s the needed part MacBook Pro 13" Retina (Late 2013-Early 2015) MagSafe 2 DC-In Board and here’s the guide you’ll need to follow MacBook Pro 13" Retina Display Early 2015 MagSafe DC-In Board Replacement