Macbook Pro 3 beeps - Actually Mojave - Not Ram

I felt compelled to write this in the hope that someone else will hopefully benefit and not give up on a broken Macbook.

I have a late 2013 15" Retina Macbook Pro with the soldered in Ram. I recently upgraded to Mojave and for a few weeks it ran with no problems. Then the macbook would suddenly just crash and power off for no reason. It became so frequent that I was lucky to have the laptop on for 5 minutes without a crash.

My first step was to open the macbook and clean it thinking that this might be causing overheating. When I put the Macbook back together I had the 3 beeps which indicated it was RAM, and as we know the RAM is soldered on these models - so basically i was looking at a new logic board. OUCH! (I was really upset my Mac had died!)

I didn't touch my laptop for two weeks or so, and to my surprise - it powered up no problem when i first tried?? However the 3 beeps soon returned when i powered it off and on again. Just having this glimpse of life inspired me to do more investigating.

It would seem every time I disconnected the battery for 10 minutes or so - it would boot fine, I could even do a restart no problem but a cold boot would invoke the 3 beeps again.

The next thing I did was roll the OS back to El Capitan and to my surprise the laptop is operating perfectly. It has been a few days working with no problems at all.

To say I'm chuffed is an understatement as I was ready to throw the laptop in the bin. Hopefully someone out there will appreciate the above.