LDR Pre MkII - LDR volume control and I/O switching

Hello, recently completed this as upgrade over the first version, as my unit was one of the very few, not imposible, but difficult to calibrate.
Now on this new MK2, I hope getting help to fix, as is stuck on ERROR 20: LDR or Relay Power Failure.
But power supply is everywere strong at 5v. I measured:
R+= 130mA (85mA idle)
O+=20mA
D+=22mA
A+=6,4mA
I fixed a missing ground pin conexion on Oled input power shocket.
 

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There isn't resistance readings on any LDR.
I tested volts also:
Rsh= 5V.
Rse= 0V.
Lsh= 0V.
Lse= 0,4V. and decreasing.
Yes Indeed, there is smd footprint.
Now I am going to populate properly with brand new FDV301N.
Smd parts are so small, I even didn't see them on the parts bag back then, when populating the board.
And remove those adapters and fets I took from VxD board.
 
Hello Zeb, my repair is getting worse, now is a short on D+, that prevents power on that track.
I think cause was placing a 1000uF fully energized on C30 part holes... and while the unit is on! I know, I know... my fault!!!.
Now the short did'nt dissapear till removal atmega328pb-u ic from the nano board. I hope a replacement of entire flashed nano is available. Also, please do you have four LDR for me?
Jordi
 
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I have learned from a youtube video, how to test LDR safely by using two multimeters. Confirmed I had three LDR placed backwise, by cause they come without dot mark (from xina). Now is fixed, all four are ready and waiting to receive the package with new nano board.
 
Morning I received new nano pcb, thanks Neb.
Sadly is still issues, now is not working the Oled display, and nano board enlight a warning red led light on RX placement. Which dissapears when display is unplugged.
I have another oled display as replacement, model ssd1309, but not sure if it is in need, because I found weird voltages on Oled output pins:
Ground pin is 0V., but on all other pins SDA, SCL, BKL and VCC is present 5V.
 
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