Advice Wanted, JBL Subwoofer E250P, fire on Amp Board :(

[Way2Cool]

Hello All,

I have a JBL Subwoofer model E250P made around 2007.

The output power to the speakers stopped earlier this year.. I had a smaller Sub and swapped them as a temp. measure.

So today I removed the Amp assembly / input panel just to observe if there was something obvious like a fuse or something like that.

The only fuse is still good.. but there was a fire inside. A blue barrel looking thingie with a cross hatch on the end facing up appears to have burned up and leaked, then possibly caught fire.

So I'm wondering.. the circuit board is burned on one side, but maybe repairable, and the part might be replaceable..

Could I just clean up the mess, buy a part and install it for testing? or is that dangerous?

Everyone jump in here and add your advice please. I'd love to send it somewhere for repair but .. I work at JBL (Harman) and speaking with the new E Lab guys.. they don't sound very promising.

I'll see if I can add a few photo's of the questionable areas and parts..


HERE'S THE BACK SIDE OF THE BOARD:

http://i191.photobucket.com/albums/z...018_162815.jpg

CLOSER VIEW OF THE BURNED AREA:

http://i191.photobucket.com/albums/z...018_163723.jpg


AND HERE'S THE LITTLE BLUE CULPRIT ON THE OTHER SIDE :

http://i191.photobucket.com/albums/z...018_163824.jpg

ANOTHER VIEW OF THE PART :

http://i191.photobucket.com/albums/z...018_162741.jpg

[Enzo]

That is SERIOUS damage, and not trivial to repair. Aside from repairing or working around the board damage, you also have no doubt some serious electronics issues.

Since you WORK at JBL, talk to the SERVICE people, not engineers, and ask what they think. I hope you have access to employee pricing, if not outright accommodation. ask them if a board swap is available. If I had a new board available to me in this case, I'd probably go for it rather than trying to make all manner of repairs. My labor time is expensive.

Yes, you have a non-polar electrolytic cap that failed, probably from some painful voltage applied to it by some other circuit element.

[Jazz P Bass]

That is a 'board replacement' item for sure!

You can't shine sh*t.

[Way2Cool]

Thanks guys.. for sure I'm trying to find a fresh board but it's not likely.
Even getting hold of the completed assembly is posing problems and also not likely.

What advice would you give for trying to clean up that burnt mess? It looks a bit like caked up corrosion as well.. like something leaked and then caught fire.
I want to go at it slowly and carefully just in case this is my only option.

[g1]

Since you WORK at JBL, talk to the SERVICE people, not engineers, and ask what they think.

It saddens me to think that this may be a 20th century notion (that they actually have service people).
More likely it is all out-sourced.

[Jazz P Bass]

So it appears that the NP capacitor that failed was C72. 6.8Uf/ 100V NP.

Jbl-E250P Output Filter.pdf

Looks like it is a part of the output filter (Class D amp)

Here is the complete schematic: Jbl-E250P.pdf