Jbl eon510 help!!

[angelothewolf]

Hi, im trying to repair this JBL EON 510, and honestly i have not too much experience with this kind of technology which involves switching PSU and class-D digital amplifier.

The equipment is not turning on. No signs of burning or defective components at simple look.

With SMPSREF as reference ive got 156VDC on VBULK. I guess this is correct, but im not getting the "+15V CONTROL". I could trace this down to U608 who seems to be responsible for regulating de 15V its a LNK304 regulator. i unsolder that one and measure 40ohm between drain pin and source, so i replace it with a LNK362. Powerup, and nothing happens, im still not geting the +15V. im getting 156VDC on Drain pin and 0 at Source pin, the surrounding components were checked (off board) and are all ok. So i will appreciate very much some help on this one!

Regulator datasheets:

LNK304> http://www.hqew.net/files/pdf/FERYST...key=LNK304-306

LNK362> http://www.powerint.com/sites/defaul...lnk362-364.pdf

[drewl]

hey, just worked on one.

If there is a problem in either of the power amps the unit will go into "protect mode" and not turn on the 5v and 15v power supplies.

[angelothewolf]

hey, just worked on one.

If there is a problem in either of the power amps the unit will go into "protect mode" and not turn on the 5v and 15v power supplies.

So, maybe the problem is in the amp section. And where is this protection circuit?? i cant find it... and what was the problem on that one you worked on??

thanks for the reply!!

[Jazz P Bass]

Call Crown & see what they want for a replacement board.
As I recall, it is not that salty.

[Enzo]

I think the point was not to locate protection circuits, but to check the power amps for gross problems like shorted output devices. Also on the SMPS itself, always check the secondary side rectifiers for shorted.

[drewl]

The output FETs in the tweeter channel were bad, and while checking out the power supply I heard a "pop", saw a flash and the supply blew out the bad FETS, so they were no longer loading down the power supply.

look underneatch the board near the output coils, you will see 2 rectangular metal FETS, I'm betting at least one is shorted.

[vjblaze]

Hey guys did we ever find a fix for angelothewolf's problem? I'm currently having the same issue and it seems like such a waste for what would be a minor repair if we could source the problem.

[angelothewolf]

Hey guys did we ever find a fix for angelothewolf's problem? I'm currently having the same issue and it seems like such a waste for what would be a minor repair if we could source the problem.

Hi there! was a long time ago, but as I remember we end up buying a replacement amplifier PCB> LINK

[vjblaze]

Hi there! was a long time ago, but as I remember we end up buying a replacement amplifier PCB> LINK

Thank you so much for the fast reply! Today we removed and tested everything except the micro resistors...spent 2-3 hours with an expert technician and still didn't find the problem. We do know all the major components are good, except it's stuck in 5v protection mode keeping the rely off.

He had another speaker JBL EON 515XT at his shop since two days ago with the same problem. He says the main issue with these speakers/boards are the extremely small resistors and the amount of time involved to remove and test every single one of them.

Seems like a huge waste to me and for the money they want for just a replacement board i could almost buy a like/used speaker. I guess I'll just keep this around as a backup since I hate to contribute something like this to our landfills!

Btw, JBL's partner here in Germany Audio Pro Heilbronn Electroacoustics GmbH wants 306€ including VAT and shipping for this replacement board, SMH!!!

[J M Fahey]

Today we removed and tested everything except the micro resistors...spent 2-3 hours with an expert technician and still didn't find the problem ......... We do know all the major components are good, except it's stuck in 5v protection mode keeping the rely off.

He had another speaker JBL EON 515XT at his shop since two days ago with the same problem. He says the main issue with these speakers/boards are the extremely small resistors and the amount of time involved to remove and test every single one of them.

Seems like a huge waste

Sorry but that´s an very slow and unreliable troubleshooting method.
And removing everything to be checked "outside" can do real damage.
Whatbyou must do is *functional* testing, esure voltages, if needed scope waveforms, and get an educated guess as of in what area the failure exists, which may not even involve a "bad part" at all.

Once you focused on a small part of the circuit, then can you measure around.

Otherwise it´s similar to finding a name on an unsorted phonebook, only knowing "it´s there somewhere".

[The Dude]

I agree with Juan. It's no different than basic troubleshooting of anything else. We don't just randomly remove parts and test them, especially when there is a schematic posted in the thread. Visual inspection for burnt parts, Check for working power supplies, Check voltages on output devices, etc., etc. You need to methodically fly down into the forest and figure out which tree is the problem instead of just uprooting all of the trees.

[Telesis]

I had literally the exact same problem as Angelothewolf and I was successful at finding the problem(s) and repairing the unit. I'll let you know what fixed it first, and then if you'd like to know how I troubleshot the problem, read on! In short, U603, the half bridge gate driver had a partial short which also took out U608, the DC to DC converter. I replaced U603 first and while that eliminated the partial short, I then replaced U608 and voila, we are back in business. <$3 fix!

HOW I FOUND IT: After measuring a proper Vbulk entering U608, and no 15V output, (and taking into account others replaced U608 with no success), I figured something was probably shorted and keeping U608 from turning on. I chose to find it passively(power cord disconnected) by measuring the DC resistance to ground starting at the +15V Control point. I measured 19ohms. Since 15V across 19ohms would draw 790ma, and since U608 is rated for <200ma output, it was clear something was amiss(partially shorted). To verify the short wasn't coming from U608 itself, I measured the resistance right at the output of U608 and it was measurably higher, indicating the partial short was on the 'load side' of L603. I have successfully traced the location of shorts using a high resolution ohmmeter and touching pcb traces and watching the resistance changes. However in this case that proved unreliable because the +15V Control signal was only used in a very small physical are of the board. (this technique works better for me on bigger thru-hole component boards)

So I resorted to another 'tried and true' method which I call "look for the heat" ;-) I connected a variable DC power supply to the +15V Control point and ground and slowly raised the voltage while monitoring the current (again, passively, no AC supplied) Sure enough, Ohm's law was still valid and as I approached 10 volts, the current was just passing 500ma which I figured was enough to generate heat I could feel, so I shut the supply off. I had already traced everywhere +15V Control was used and so I turned the supply back on(set for 10V) and touched each component that connected to +15V Control, and then shut it off. I didn't want to burn a trace off the board. After several checks I found U603 heating up quite hot when the supply was turned on. Bingo.

I ordered a couple U603's and a couple U608's (just for insurance) at Mouser. I also ordered a ChipQuik SMT repair kit which I hadn't tried as I have a hot air rework gun. I replaced U603, and measured the DC resistance from +15V Control to ground and now it was sitting at 1.25Kohm, much better! I powered up the unit and still nothing out of U608, so I went ahead and replaced it, and now it's good as new!

Sorry for the long diatribe but I thought others may benefit from my toils. Also, after having tried the ChipQuik method for SMT removal, I'm a believer. I highly recommend it. It worked fantastic. Even though I've had excellent success with a hot air rework station, the ChipQuik system is pretty slick. I won't bore you with the details here as there are multiple YouTube videos on the subject. I will likely use this method over the hot air system as you have more control over the heat! Check it out!

Well that's all folks. One repaired EON510. Special thanks to Angelothewolf for posting the schematic and parts layout. I couldn't have done it without it! I'm happy not to have bought a $250 replacement board and getting away with a couple bucks in parts and some good old fashioned troubleshooting!

[bigdrums925]

I am having problems with the startup on a JBL Eon510 also. I happen to have 2 boards for this particular speaker and have replaced Q505 & Q506 on each of them. They were shorted. But so far no startup. I have read the solution outlined above but frankly its a little over my head. I have checked the voltages on U603 & U608 which at the time showed about -104vdc on each of the 7 pins. One is +104vdc Seemed odd and I'm not sure I was measuring correctly. I was wondering if anyone here might guide me through this?

[bigdrums925]

anyone?

[bigdrums925]

what should the vbulk be on this amp?