SOLVED LED always lit if input or output jacks are touching the enclosure

[FamousAmos]

I am having a weird issue I have never experienced before and hopefully someone can set me straight. Just finished an ADHD board with the buffered foot switch add-on. Everything is working perfectly function/soundwise except the LED engagement/state. Pedal turns on and off as it should but the LED is consistently lit. I have narrowed it down to the strangest issue. The LED on off works as it should as long as the input and output jacks are not touching the bare metal of the enclosure. If they are touching it then the LED stays consistently lit regardless of if I click the foot switch on or off.

It is certainly and undoubtedly the input output jacks as I can move them while the pedals powered on, touch the enclosure with them and the LED will light up, move the jacks so they're not touching anything at all and the LED turns off, and clicking the foot switch turns the LED on/off as it should as long as the jacks are not touching the bare metal of the enclosure.

What is going on lol

 

[FamousAmos]

 

[Nostradoomus]

There’s a grounding problem somewhere, I’d start by reflowing your 3pdt+AK pads they look pretty cold. And the 6 pads connecting the main/bypass board on the back too.

 

[FamousAmos]

I reflowed them all on both ends/sides, cleaned the hell out of it and still the same issue.

 

[Alan W]

If you only have one of the jacks touching the housing, does it still stay lit?

 

[FamousAmos]

Yes, either one of the jacks one at a time and/or both touching the bare metal of the enclosure at the same time turns the LED on

 

[giovanni]

The solder joints look good to me. If this is consistent the short must be very obvious. Do you have a metal bezel touching some traces or something like that? I had that problem once.

 

[FamousAmos]

Ok well problem solved it was absolutely something with the LED itself. I ripped it out and just totally replaced it with a new/different one and it works exactly how it should now with switching on and off.

I have no idea exactly what was going on but possibly like giovanni mentioned perhaps the metal bezel, or stem, or something with the LED was shorting out against the enclosure and when the jacks touched the enclosure it was competing the ground short circuiting issue. I've never had a problem before with the LMS prebuilt LEDs. Oh well, thanks all.

 

[Robert]

Sounds like the cathode side of the LED might have been making contact with the metal housing internally.