Not all LEDs will turn on...but they will

Projects General Guidance
1

I'm having issues with an LED project of mine. I'm creating a wood wreath outlined by green LEDs. I have 120 LEDs on the outer ring and 42 on the inner ring. The inner ring is divided in to 6 circuits and the outer ring is divided in to 12 circuits. Before i connected everything up to the transistors and Arduino i powered on each circuit, so i know they all work. I have all the anodes connected together and am controlling the LEDs on the cathode side. I hooked each circuit up to a 5.1k resistor then to the collector of a 2n2222 NPN transistor and connected the emitter to ground. The base of the resistor has a 1k resistor before going to the Arduino.

My problem is that when all connected, not all circuits will turn on. Such as, circuits 2, 7, 8, 10 of the outer ring and circuit 6 of the inner ring.

I have a 12v power supply for the Arduino and an 18.5v 3.5A power supply for the LEDs all on a common ground.

if i disconnect circuit 6 (working) and 7 (not working) from the resistors and switch them, then circuit 7 will now light circuit 6 LEDs, but circuit 6 still won't light circuit 7 LEDs. ????

Is there something i'm missing? If i disconnect everything from the transistors/Arduino, they all work with direct power, so i'm completely lost at what it could be.......

Pictures attached.

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2

I can't tell much at all about your circuits from your pictures.

Maybe the way you have the Arduino pins connected to the transistor bases is pulling too much current? Perhaps use FETs instead of BJT's?

3

A drawing (schematic) will help a lot more than photos.
If you didn’t do one already, it’s a great way to document and debug your construction.
The issue could be as simple as an open 0V/ground somewhere - or as mentioned above insufficient grunt to drive you LED circuits.
Hopefully the output pins are all ok.