Can't get rid of undervoltage errors

What is the problem?

I am getting undervoltage alerts

What did you already try to solve it?

I started off with a RP3B+ kit that included a Vilros 2.5A power supply. When that had issues, I bought a 24v to 5v converter 3A and that is also having the same issue. I also tried swapping in another RP3B+ and that didn't help solve the issue. The usb cable I am using to power is the one that came with the buck converter....I cut it in half and it seems thick. I measured voltage with multimeter and it is perfectly steady at 5.08

Here it the converter :

Complete Logs

octoprint (2).log (261.3 KB)

Additional information about your setup

I am running a pi cam v2.1 and a 5v fan off the pins. I also have it connected with to the printer with a usb cable but I have tape over the power line.

I can't keep throwing money and time at this issue...its driving me nuts. I don't know how to fix this and I would appreciate any help you can provide.

First, unplug everything from the Pi. Unplug the camera, fan, printer, everything. Sometimes these things can draw too much, whether they are rated too or not. Best to test with the minimum number, then for example when you add in the fan and it goes wrong, you know the problem.

I personally avoid converters, since they can't usually hold the voltage when under load. When you measure the voltage, measure across the GPIO pins - see and find the 5V and GND pins. There is some voltage drop by the connection to the Pi and it's internal circuits, internally the voltage must go below ~4.6V for it to start complaining.

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I was using a 5A led strip power supply, and was having a lot of problems like you. I was also using a cable that I thought was good enough, and was not blaming it, but in the end I´ve found out that the cable was the problem. I´ve soldered 2 thicker wires directly to board pins, and the problem has finished.

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I´ve soldered 2 thicker wires directly to board pins, and the problem has finished.

What board pins do you solder too?

Have you tried covering the “ extra “ pin.
You only need the data lines connected.
I put a piece of Kapton tape over the +5V usb pin and the under voltage warnings went away.

Hope it helps


To pins 4 nd 6 of this picture: