Trouble tracking down bad RAM in a Lisa 2/5

[redruM69]

I recently acquired a Lisa 2/5 as a project.  PSU fixed, corrosion repaired.  It has 2x 512K RAM cards in it.
Getting an error 70.  I have narrowed it down to 1 card.  The bad card is in slot MEM 1, MEM 2 left empty.
Enter service mode, Read memory location $186 gives 0000 0000 0000 0004.  Cool!  From what I read, that means the chip at Row E, Column 20 is bad. 
Replaced the HM4864P-2 with a now socketed Fairchild MB8264-20, which I believe to be compatible.
Still get error 70!
Memory location $186 now gives 0000 0000 0000 0404
So it appears that not only did the RAM I replace still not work, but now i have a new bad bit on column 3 row E?

Thoughts?
 

 

[redruM69]

Update: RESOLVED!

I made an error/typo with my original assessment.  It was column 3 the entire time.  I wrote down the wrong value. :x  
This means I accidently replaced the wrong chip!  It also appears the MB8264-20 is NOT compatible.  I stuck in an NEC D4164D instead, and it worked fine. 
Replaced column 3 row E with another D4164D, and no more errors!
 

Now to move onto the floppy drive not working!

 

[MOS8_030]

Update: RESOLVED!
 

Now to move onto the floppy drive not working!

Congrats!

Good luck with the floppy drive. I gave up on mine. Even with a different drive I still had issues. I think maybe the Lisa Lite card has a problem.

 

[redruM69]

I haven't looked at it close yet, but its not auto-injecting.  I noticed one of the sensor LED's inside is glowing, so it is receiving power at very least.
What were your symptoms?

 

[MOS8_030]

https://archive.org/details/AppleLisa_RepairSunGuideDC

Download the repair guide and check out the floppy section.

It probably just needs a good clean and lube. But also make sure the felt pad is still there.

Also, you'll need some genuine 400 or at least 800K disks.