Running 2 mini stoplight components

Projects General Guidance
1

I am learning more about arduino and the digitalWrite for OUTPUT.

If I have 2 mini stoplight led components, with one running off of pins 11,12,13 and a resistor to gnd wire also, and the other running off of 7,8,10 and a resistor to gnd wire also, with each stoplight on its own mini breadboard, one stoplight component has dimmer lights than the other.

I am assuming this is due to the voltage diminishing over the second stoplight component when I try to light both greens simultaneously, both yellows, etc.

My arduino is directly connected via usb to my laptop.

Is my assumption correct?

Link to stoplight components I am talking about here:

2

No, they should not influence eachother. Did you forget to call pinMode() for the outputs?

Also, seems like the stoplight already has resistors on board. So no need for an external resistor.

3

I would check the ground wires. Sometimes those jumpers don’t make great connections. Especially if everything else is the same including the code.

As stated above you shouldn’t need a
Resistor but did you use the same size for both connections? You might need a resistor because I think I saw a 0 ohm on the green when I looked at these in the past.

4

Thank you so much for the helpful suggestions! Turns out I had 2 different resistors (a different one on each stoplight component). This is due to being partially colorblind, so that may be a challenge for me to overcome going forward. Also, I did forget to add one of the pinOUT statements. Thank you again! They are both working great now!

5

Get resistors with the resistor codes :slight_smile: i remember they used to test for color blind at electronics school. I like the number codes on the smd resistors better also.

6

I can't remember the codes and find the small rings hard to see so I check each resistor with a meter and I also keep the resistors in a small bag or something for each value

7

Buy a component tester, also known as an "Ardutester":

Sits on bench, just insert the component, latch it into the socket and press the button.

8

Oh jeeze when they get old or when different mfg have different colors... it's hard to tell the colors apart sometimes for anybody... and most times I have to say my memnomic out loud to remember what they mean... I love the online calculators!