Push buttons no longer working at all

Using Arduino General Electronics
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Hello, all. First time being on the forum.

I'm on Project 7 - keyboard instrument, and while trying to debug the input, output, and flow of the current, I noticed only one of the four buttons was working. Then all buttons gave out. Then I went back to basics with the breadboard and for some reason none of the LEDs light up. No matter which LED and which push button I choose, there is no current at the moment when I press the button. Attached is a pictures of my debugging efforts. (I can only upload one since I'm new to the forum.)

Any help would be much appreciated. Cheers.

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Welcome to the forum

It is very difficult to see how things are connected looking at your 'photo. A schematic of your project would be more helpful

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Please post the sketch, using code tags when you do

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OK, I've redone the board. Does this help?

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Here's the schematic of what I'm attempting - something fairly simple.

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6480×640 61.3 KB

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So, no sketch, just a pushbutton and LED

Try connecting the pushbutton using 2 diagonally opposite pins as 2 adjacent pins may not b switching as you expect

Does the LED light up if you supply 5V to it via the resistor without the switch in the circuit ?

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If you bypass the switch with a jumper wire instead does the LED light up?

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It does.

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Here is an attempt at passing current from 5V to ground using diagonally opposite pins as advised. Very weird. It used to work if I'd press hard enough, really hard. Now, no matter how hard I press, it doesn't make a difference.

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It sounds like the pushbutton is FUBAR or your connections to it are bad. Do you have a multimeter ?

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All pushbuttons? I don't know.

I do have a multimeter.

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Then use it to measure the voltages as strategic points of the circuit and to test whether the switches are working

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Either I have a wacky multimeter or I'm not using it correctly. (I'm not pressing the button here.)

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@UKHeliBob Now (below) I'm supposed to be driving 5V across the circuit but the multimeter shows 2.13V - 2.17V.

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5v looks correct... what did you expect?

In the 2nd photo you seem to have the battery tester setting selected?

In the third photo you are measuring the voltage across the LED. There will also be a voltage drop across the resistor.

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So does that mean that I'm supposed to see a voltage drop across the switch when it's closed?

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If you try to measure the voltage across the switch, you won't see anything whether it's open or closed

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No... because it effectively has 0 resistance. But both the LED and the resistor have resistance.

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I've had a lot of experimentors complain about bad breadboards.
If you purchased it from Amazon, ebay, alibaba, any of the Chinese webstes or Adafruit it may be bad.
Intermittent contacts or none at all.

1 Like
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@jim-p

But if I press the red lead against the positive/power end of the resistor and the black lead against a connection to the ground, I'm supposed to see something like 5V when the switch is closed, no?

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So here the switch is open, yet the meter reads 5V from the resistor to the ground.

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Edit: Indeed I did order the kit via Amazon. But why would a breadboard respond poorly exclusively to switches?

Checking out for now. Reached the maximum number of replies for the day.

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@red_car Edit 2: (regarding legs on the switches): Even though they seemed fairly short at first, it was not an issue a few days ago when the LEDs responded to the buttons.
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@red_car Edit 3: You know what? I bet the metal ribbons within the board collapsed a bit, so you may be onto something here.