HE123 MK2 No power

[glenwaye]

I have the HE123 MK2 powered up on 12v the 2x lights (beside the 4x switches) to the right of the screen (screen never lite up) was on for a bit then went out. I turned the power off thinking something was wrong and picked the board up and found around the screen area was hot to touch. I double checked my 12v connection and all is good.
I waited for the board to cool down before turning back on and now nothing is happening as in no lights and no screen.

Any ideas on what to check/test?

 

[Notenoughlights]

Can you post a photo of how it's all wired up?

 

[glenwaye]

 

[Notenoughlights]

Do either of the 2 yellow things beside the power wires (Thermal fuses) get hot when powering the board on? Do you have a multimeter on hand to check those diodes beside them as well? Circled in red

 

[glenwaye]

I have a Multimeter. I'll try is and get back to you

 

[glenwaye]

Beside the red wire is correct voltage both sides, beside the black wire is 0.032 both sides.
temp probe shows them at room temp.

 

[Col The Hammer]

Your Beagle Bone board appears to be sitting a little low in the photo. It's probably just the angle of the photo but might be worth checking the pin alignment.

 

[Notenoughlights]

Beside the red wire is correct voltage both sides, beside the black wire is 0.032 both sides.
temp probe shows them at room temp.

What do you mean by correct voltage both sides? Test with the power off on the meters diode setting, probes one way should read 0.6 approx and the other way should be open circuit, if it's 0 both ways, the diode is dead.

 

[glenwaye]

I get you question now... sorry,
beside the red wire I get 2.950 one way and 0.180 the other way
beside the black I get 0.002 one way and 0.002 the other way
So the one beside the black would be dead?

 

[Notenoughlights]

That sounds like the diode is shorted so it's conducting in both directions. Was your wiring reversed at any stage? The diode should not fail under normal use.

 

[glenwaye]

No wiring was the first thing I checked.
The only thing to me that was abnormal was how hot the screen area was when I picked the board up.
Being my first year doing Xmas lights I don't know if this is normal.

 

[Notenoughlights]

No wiring was the first thing I checked.
The only thing to me that was abnormal was how hot the screen area was when I picked the board up.
Being my first year doing Xmas lights I don't know if this is normal.

@AAH may be best to advise here as well. I would perhaps send him a private message, or use his contact-us link on his website if you can not get hold of him here, he makes the boards so will be best to advise further.
There may have been a short on the board which took out the reverse polarity protection diode by chance.
The @ mention should help him see this thread as well.

 

[glenwaye]

Thanks everyone for the help.
I have reached out to AAH via his web site.

 

[AAH]

Changeover on the way.
Definitely sounds like the protection diode went short which is what it's meant to do when there is a fault.