A11. - A7 and A1 -A0 only LED that light

[Travis Webb]

I am not sure, nut I am sure there is a bad diod and I am hoping that identifying which lights might give someone smarter than me a clue to which one is failing. 

[Johnny Billquist]

Those are the only LEDs shining, even with you lift up the lamp test switch?

Johnny

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[Travis Webb]

Yes. 

Travis Webb

KM

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[Johnny Billquist]

Bad solders, or diodes inserted the wrong way?
Because that don't like like any pattern that I can think of any other
reasons for...

Johnny

On 20/01/2026 19.35, Travis Webb wrote:
> Yes.
>
>
> Travis Webb
> KM
>
>
> On Tue, Jan 20, 2026, 1:39 AM Johnny Billquist <b...@softjar.se
> <mailto:b...@softjar.se>> wrote:
>
> Those are the only LEDs shining, even with you lift up the lamp test
> switch?
>
>    Johnny
>
> On 19/01/2026 22.29, Travis Webb wrote:
> > image.jpg
> >
> > I am not sure, nut I am sure there is a bad diod and I am hoping
> that
> > identifying which lights might give someone smarter than me a
> clue to
> > which one is failing.
> >
> >
> >
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[Travis Webb]

Agreed.  I checked all the diode.  Could be a bad solder, but I have reflowed. I was hoping the lights would give some clue on specific diodes to check.

Travis Webb

KM

[Johnny Billquist]

I was specifically thinking of the LEDs. They are also diodes.
Just looking at the schematics, there is nothing that is common and
unique to just those LEDs. So there is no one single thing you could
point to that would cause what you are observing.

If you know how read schematics, you can check youself. The schematics
are online.

Johnny

On 20/01/2026 19.45, Travis Webb wrote:
> Agreed.  I checked all the diode.  Could be a bad solder, butI have

> reflowed. I was hoping the lights would give some clue on specific
> diodes to check.
>
> Travis Webb
> KM
>
>
> On Tue, Jan 20, 2026, 10:42 AM Johnny Billquist <b...@softjar.se
> <mailto:b...@softjar.se>> wrote:
>
> Bad solders, or diodes inserted the wrong way?
> Because that don't like like any pattern that I can think of any other
> reasons for...
>
>    Johnny
>
> On 20/01/2026 19.35, Travis Webb wrote:
> > Yes.
> >
> >
> > Travis Webb
> > KM
> >
> >
> > On Tue, Jan 20, 2026, 1:39 AM Johnny Billquist <b...@softjar.se
> <mailto:b...@softjar.se>

> > <mailto:b...@softjar.se <mailto:b...@softjar.se>>> wrote:
> >
> >     Those are the only LEDs shining, even with you lift up the
> lamp test
> >     switch?
> >
> >         Johnny
> >
> >     On 19/01/2026 22.29, Travis Webb wrote:
> >      > image.jpg
> >      >
> >      > I am not sure, nut I am sure there is a bad diod and I am
> hoping
> >     that
> >      > identifying which lights might give someone smarter than me a
> >     clue to
> >      > which one is failing.
> >      >
> >      >
> >      >
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[Ed Porter]

On 20/01/2026 19:41, Johnny Billquist wrote:
> Bad solders, or diodes inserted the wrong way?
> Because that don't like like any pattern that I can think of any other
> reasons for...
>
>   Johnny
>

Looks to me like the IC is backwards

-ed

[Johnny Billquist]

Which IC, and why?

Johnny

[Ed Porter]

The only one, and because the notch doesn't match the print on the PCB.

-ed

[Johnny Billquist]

Oh? I missed that picture...

Johnny

[Johnny Billquist]

Ha! You are absolutely right. Well spotted. I didn't even think of
looking at that picture.

Johnny

[Bradford Miller]

I thought that too, but why didn’t the IC fry with power reversed?!

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[Ed Porter]

On 20/01/2026 19:57, Bradford Miller wrote:
> I thought that too, but why didn’t the IC fry with power reversed?!

Maybe it has :)

-ed

[Johnny Billquist]

On 20/01/2026 19.57, Bradford Miller wrote:
> I thought that too, but why didn’t the IC fry with power reversed?!

What says it hasn't?

But it could also have survived. We'll have to see. But it's clearly
mounted the wrong way.

Johnny

[Travis Webb]

This is why I should wear glasses when working. Ill test tonight.  But that makes sense looking at the picture.  Wouldn't be the first time and wont be the Last. :(

Travis Webb

KM

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