Keyboard not working on Dell Inspiron 15 5000 series

After installing a SSD drive in my Dell Inspiron 15 5574, some of the keys on my keyboard stopped working.  After a few hours of troubleshooting, I finally noticed that the ribbon cable connecting the motherboard to the keyboard was loose from its socket.   I popped it in and everything was ok.  I have no clue how it worked itself loose.  Probably it was not inserted correctly from the factory.  This photo was taking when I first opened the case.  If you zoom in, you'll see the ribbon cable is not inserted fully.

MtnSquid, thanks so much. Half my keyboard stopped working. I saw your post. Removed battery, held power button for 15 seconds, etc.... When it booted back up, keyboard now works.

Thank you, thank you, thank you for posting your solution!!!!

The left part of my keyboard was like "paralysed" some keys weren't working properly and I had some troubles to lid up the caps lock key and the letters s, a, i, sometimes, the numbers too were to difficult to make them working well. To be honest, i was planning to buy a new keyboard. However, thanks to this post, that solution's worked flawlessly. The only part that was boring for me was, to unplug the battery cable from the motherboard. If you have short nails, it will take a little bit your nerve. But in the end, I sorted it out. Like, less than 5 min my keyboard was completely functional as new one.

Thanks for the solution 

THANK YOU for posting this fix!  My keyboard just quit responding right in the middle of typing and thankfully found this thread on my phone.  Did it, and it worked like a charm.  Thank you for sharing your solution.

Thank you so much for this post, I'm now able to use my keyboard on my laptop for the first time in months thank you 

I tried to unplug the battery then remove the keyboard pins (blue ribbon cable) from the motherboard and plug it again. This solved the issue.

Hope that helps

I also own an Inspiron 15 5000, and have tried this method three times. It has not solve the problem, the y i o p j k l m keys do not always work. If this is a bios problem them why doesn't DELL send an update.

I do not have this problem with my HP and Acer laptops. Considering how much I paid for my Inspiron, I am not happy with having to use a wireless keyboard. It is no longer a laptop, which defeats the reason why I bought it in the first place. 

Sure worked for me! Other solutions were too involved and I was skeptical. This fix was easy!

Thank you, worked perfectly!

This suggestion worked for about 2 days and then certain keys stopped working again.  Have also downloaded/installed current drivers.  Keys still not working reliably.

Hi,
I don't think its either a "battery disconnection, bios or power drain" issue.

I have Dell 15 5000 laptop since 2020 and recently, less than 10 days back, I started noticing my (c, v, m, ,, ., ENTER and left shift) keys stopped working. I had to press others keys, later I learned the adjacent keys to the problematic ones, in order to get them to work.
When working they would work fine and after some time would go back to same issue or after a restart it would happen.
I opened and cleaned the contacts, interestingly the insides are as clean as day 1 since this laptop is for my office work only and mostly remain in one place. Anyways, the connections were fine and nothing looked odd.
After restart, it worked fine for some clicks before going back to original crisis.
This time, since I had to work, I connected an additional mini-keyboard to continue working which is working perfectly.
Being a little tech savvy I was skeptical it being a hardware or power related issue and being an oldskool computer user, I was tempted to reinstall each and every software after a deep format. However, being a curious oldskool, I was also trained to try layer by layer to see if we can find out what could be the problem. So I did the next logical thing before formatting/reinstalling the software.

I uninstalled the keyboard drivers and then "uninstalled the hardware"; both from 'Device Manager'.
The laptop rebooted, reinstalled its own generic keyboard driver without asking and EVERY KEY IS WORKING FINE.

The usual time for recurring of key errors is over by many hours now (not days), the laptop has been restarted twice for normal workings (and not for testing purposes) making this a 3rd session and its still working fine.

Try this first before going to other solutions.
If this works for you, please do leave a comment stating your experience for others facing this problem.
Because if this works for everyone, then its keyboard's driver issue and not a hardware or power related issue.

Good luck.

Worked. But, just to be clear, I disconnected BOTH the main battery AND the CMOS battery.