D1 Mini and Relay Shield works when wired directly but not with pin headers

ESPHome
1

Hi, this issue has been driving me mental. I have a D1 Mini and Relay Shield powered by USB to open/close a dry contact circuit. I’m using ESPHome for the code side.

When I wire the D1 Mini to the Relay Shield directly (5V, GND, D1), it works with no issues. I can hear the relay click and it does what is expected. However, when I use the pin headers or a breadboard the relay isn’t working. I can connect to the D1 Mini and attempt to toggle the relay but nothing happens and I don’t hear any click from the relay.

What I’ve tried so far;

  • Breadboard with no solder, testing continuity with a multimeter.
  • Pin headers with no solder, testing continuity with a multimeter.
  • Pin headers with solder, testing continuity with a multimeter.

My best guess is that it needs more power or something but I’m not sure where to go from here. Any advice or suggestions would be appreciated.

2

The shield is supposed to be plugged into a header socket on the Wemos D1 Mini, so I am confused where the breadboard comes in.

3

Ah I wasn’t clear. I tried the breadboard as an alternative because the shield does work when connected directly to the D1 Mini with cables. Once I introduce the header pins OR the breadboard, I get nothing from the shield.

Does that make sense?

4

Yes. Now show a schematic of your connections. Please, not a useless Fritzing picture.

5

It seems strange to even try that, pin headers need to be soldered, both on the Wemos side and on the shield side.

Also, pin headers make a “shorter” connection than wires, so I don’t see how it can be a power issue.

6

I suppose I was hoping to test them prior to soldering. Can pinheads work without solder in that case? Maybe I need to re-solder.

7

Not reliably. Just to be clear, I’m talking about the connection between the (m/f) pin header to the PCB’s.

8

Maybe the shield have pin with not connection.

Check the pins connectivity

9

I know the pin headers make a “shorter” connection than wires but is it possible that the other pin headers are using power or causing an issue? When the D1 Mini and the Shield are connected via wires, they are the only connection points if that makes sense?

10

I’ve never had any issues with pin headers. But as suggested by @MiguelAngelLV , it may be worthwhile to check if the pin headers are okay and make a solid connection on all required pins.

11

@robertklep @MiguelAngelLV @stevemann , thanks a lot for your advice. Have it working now. I resoldered the header pins and it is working. I know in the future that connections NEED to be soldered. I thought you could connect them for testing and then solder after it all works.

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