So this is my first time using altium designer and below is part of my schematic where the board receives 5 input signals from another device, which will determine whether or not the diodes light up. I1, the edge connector, I had to add to the library myself as there was not a component for this.

enter image description here

However, when on the PCB Editor, there is no connection line between Input Logic I1 and the 5 diodes like there is in the schematic. Additionally, I cannot connect the diodes to the input logic in the PCB.

enter image description here

How can I

  1. Make the connections correct or
  2. Get altium to ignore what connections can/can't be made and just let me connect I1 to the diodes

Thanks in advance,

  • 2
    \$\begingroup\$ Are you sure the components are connected? The wires at I1 look strange. \$\endgroup\$
    – asdfex
    Commented Jul 22, 2021 at 11:31
  • 1
    \$\begingroup\$ Are the diodes D1-D5 are connected to L1 on schematic? I dont see pins of the L1 connector on schematic \$\endgroup\$ Commented Jul 22, 2021 at 11:34
  • 2
    \$\begingroup\$ @bobtllama I am not sure about Altium specifically. But normally, you need to make sure the wires and the pins just touch each other. They shouldn't overlap. The wire should stop where the pin starts. Some software will not detect overlapping wires as connecting. \$\endgroup\$ Commented Jul 22, 2021 at 11:44
  • 1
    \$\begingroup\$ Remove the wiring from the I1 connector (or just pull them out of the way) and this should reveal the black pins of the I1 connector. Then take the wiring and connect the ends of the black pins of I1 to the wiring respectively. When you compiled the schematic did you get any errors suggesting some pins are not connected ? \$\endgroup\$
    – citizen
    Commented Jul 22, 2021 at 11:53
  • 1
    \$\begingroup\$ Go through a tutorial on creating a component (for both schematic and PCB) and using it on a trivial schematic and PCB. Then come back to this knowing how schematic pins tie up to PCB shape pins. \$\endgroup\$
    – user16324
    Commented Jul 22, 2021 at 12:14

2 Answers 2


The pins have "hot" end that you can connect to and that has to be oriented correctly.

Here is what it looks like when not selected:

enter image description here

When you drag it, the cursor jumps to the "hot" end and a crosshairs appears at the end.

enter image description here

This is the end you connect a wire to in the schematic.

It's important to realize that the rest of the "pin" is just cosmetic, unlike wires drawn in a schematic.


You have the pins on the connector schematic symbol turned around, so the end you are supposed to connect to are up against the yellow box part of the symbol instead of pointing out where they are easy to connect to.

Unfortunately Altium doesn't make it super obvious which end of the pin is which in the schematic symbol editor but if you give the pin a name (like "D1", "D2") then the connectable end is the one farthest from the name.

(I'm assuming that the pins are named as "D1", "D2", etc, and numbered as 1, 2, 3, 4. The names should normally be inside the symbol box and the connectable ends of the pins pointed out. You could make it more clear by making the pin numbers visible on the schematic)

  • \$\begingroup\$ i've re-orientated the pins but this still doesn't seem to fix my issue (and also have checked that they are indeed connected) - maybe there's an issue with altium not realising what on the footprints corresponds to the pins? \$\endgroup\$
    – bobtllama
    Commented Jul 23, 2021 at 14:12

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