Noob user, issue with PCB changing net ID

Hi Folks,

I’m following a tutorial to design my own PCB with Kicad. I’ve gotten to the stage where I am about to add the ground layer, but I’ve realised that all my ground pins have changed to +5V and not GND. I’ve had a look back in my schematic and the GND pins are labelled as GND. What have I done wrong here? How can I revert it back?

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Have you selected the GND power symbol and the 5V power symbol in the schematic?

Be sure you do not have a shortcut between GND and 5V

This is the probable reason.

Try to run the ERC on eeschema and make sure it is happy.

If a net with two different labels is created in KiCad, then the nets are merged silently, and KiCad just picks one of the labels (I think alphabetically) as the net name.

So if you create a short between “+5V” and “GND” then these just get merged. There may be an ERC error, especially if both nets have a power output (an important reason for the “PWR_FLAG” symbol).

The location of such a short is often hard to spot. A common mistake is to draw a wire right through an schematic symbol (for example a decoupling capacitor).

One way to spot these is to looking for unexpected junction dots on the pins of the symbols. See screenshot below.

This short is caught by ERC because both nets have a PWR_FLAG, and thus a power output pin. If one of these PWR_FLAGs is missing, then ERC does not catch it.

While making connections in the schematic, you might have shorted +5V and GND. Identify that net and simply remove it. And if it is not the problem, then update the netlist and import again.

@Amit_Bahl You no longer need to generate and export a netlist (This has been so for the last couple of years). The netlist export has only been retained for use in external tools. You need to update the board from schematic to achieve this.