Repair ZP120

It’s hard to know what symptoms a blown chip would cause.  I once had blown amp chips that went in such a way that they lost some of their pins in the process -- literally blown off.  In something like that, the traces could be damaged, it could cause shorts elsewhere… It’s just too hard to know for sure what to expect.

That section is the 36v supply.  If you are familiar with the primary side voltages, the power path from input 120/240v is rectified and passed through a dual inductor and 320v dc is produced which is available on pin 5 of the primary side of the tarnsformer.  Somewhere around the mosfets that are part of the doubling circuit that generates 320v, the circuit apparently branches and feeds into the 36v supply section you identified (I’ve never looked at where this happens in the zp120).

I just looked at that section on a board… it does look fairly straightforward.  What I mean by that is that it should be possible to check many of the components.  Bad diodes, capacitors or even open windings can all be looked for in circuit.  The 3 pin devices that look like transistors are actually dual diodes and those diodes can be checked too (use diode test between the middle leg and each of the outer ones).

I have some zp120 devices that have the same symptoms you describe -- i just haven’t invested time in looking much further at this point.  I have fixed a lot of the older zp100 devices, and they had similar voltages.  In those, the 36v would be unavailable when in standby and i think the zp120 would be the same.

Please post back here is you find anything (good or bad).

ITS THE DAMN RISER BOARD! I'm so happy, and at the same time mad at myself for not trying that when I tried a known good logic board. 

with the repaired power supply, known good riser and existing (from the bad unit) logic board, I got my 36V and sound. 

Now to dig and compare what's wrong with the riser board, or buy one of they're available. 

Wow -- that’s excellent to hear.

This is right above the smaller connector of the riser board (j18001). I found a short on pins 2/3 of Q18005 removed it and eventually traced it to a shorted D18020 right in front of it. D18020 is labeled D3 with a sideways 13, which I think is the date code. I believe it's a zener diode but not sure. Will try a few things and report back. 

That was it! I replaced the shorted diode with a 1n4148 as that's all I had on hand. No more orange light and she sings! 

I have to thank everyone that participated in this thread, wouldn't have gotten her working without your help. 

Congrats!

It looks like that component may be a zener with a working voltage of 2.1-2.3V (google philips bzx399).  The 1n4148 is a switching diode, so it might behave a little differently.  For example, the 36V section may be constantly ‘on’ rather than off during standby.  If you get any more issues you may want to find a more similar part.

I had a quick look at my units that have been having similar issues, and sadly this part is fine on them.

Thanks for closing the loop on this. 

I'll check if the 36v turns back to 15v at standby. It's only temporary until I find the matching part..

Have you tried yours with a known working riser board and logic board? I'd like to still know more about the orange light error. Seems with all voltages correct the orange light refers to the riser/logic board or amp chips.

I have a Gen 2 Play 5 that has a short on the power supply. Doesn't seem to be much info out there on them. 

Here’s a similar issue that your info helped me solve (I’m 99% sure)...

This is the same board that I posted an image of a couple of days ago.  I had replaced some damaged components, and after that it would do the white/off/yellow/off cycle when I tried to play.

The 2 traces that run vertically between the transformer on the left and the two grey capacitors on the right connect two pins from the riser connector up to the MOSFETs above.  They are damaged (confirmed with a continuity check) - it looks like the power surge the board suffered must have caused them to blow up.

I wouldn’t have found this so quickly without your success, shtnarg!  I imagine I’ll have to replace that crispy looking R16010 on the top right as well -- it seems to be in the path back to the riser connector.

Yes I have seen the 36V fall back.  It doesn’t happen immediately but it does eventually.

My issue is on the power/amp board - see my other recent post.

I have a few gen1 play:5s but no gen2.  The gen1 play5s are actually pretty horrible to try to fix.  There is a massive buildup of heat in them when they are in use, and it causes a variety of different failures.  The enclosure is basically a box with only one small bass reflex opening -- not great for air circulation.

Well done! 

I put mine back into the shell to clear it off my desk. Forgot the volume/mute buttons, so I did that twice, including those F****** clips! 

And of course the orange light is back. 

sigh