Powermatch PM8500 turned off Screen

I have a Powermatch PM8500 amplifier, and its  Screen is turned off , but i can to communicate with the ControlSpace software, i've done the firmware upload  via Recovery mode, turned on just the leds light indicator during the process, on computer  worked well. The same amplifier had a surge voltage before, and i 've found a burned  I.C TNY280G , its function is  start up the amplifier, so I  fixed it, i'm a maintenance electronic Tecnician  here in Brasil, by Loudness Company. I'd like to find a service manual, or any detailed explanation about this problem, coud you help me guys!? 



I ran into to exactly the same thing, could it be a design problem?

The tny280gn was blown as well as the fuse. Replacing it turns on the 9.5Vdc rail as well as the 3.3Vdc on secondary side and the 5Vdc on the small daughter card on the primary side. The three LEDs lits up on the front and you can put the unit into recovery mode(the faults led turns on) and you can talk to the unit over USB and do FW upgrades, but nothing more.

The rest of the power supply card does not start as the signal from the "main" card that enables(via a set of optocouplers) amongst other the 12Vdc section of the power supply is low.


Would very much like to repair it as it's out of warranty, it would be very helpful with the schematics or at least the pin-out of the connector between the main card and the power supply card.








I have the same problem, except from the burnt out TNY280GN. One day, the PM8500 just died.

The backlight of the display is on, but nothing on the screen. After a short while, the fault LED comes on. All other LEDs are on all the time.


I have tried connecting to the service serial-port on the mainboard, but I can't get the serial-settings right.. Only mumbo-jumbo coming out on the terminal. Does anyone know the correct serial-setting or if it is a specialized serial-protocol/BUS?



Apologies for the trouble. 

For this symptom, I would advise contacting your local sales engineer or support rep to set up service for the amp. There is no quick fix for this type of issue, and if the amp is in warranty it should be replaced.

We also do not have serial settings for board level components, but this would likely not help with a solution. Again, I'm sorry for the inconvenience. 


Best Regards,





Hello Chris, and thank you very much for your reply!


After connecting to ControlSpace i get the error: power supply fault - ICV not OK

The amp is on fw 3.660.

Since I posted this question 2 more of these PM8500's have become faulty aswell.


I have read that this "ICV not OK" -fault often lies within the FW, and not with the electronics. Can you confirm this, and is there any meassurements on the PSU I can make to rule out one or another? what voltage does the ICV refeer to? (if not all) 

Our local sales rep. only tells us that they are broken and we have to buy new amps as none of them are within warranty. But I am finding this very difficult to accept for a product in this price-range. So any info about ICV-failure would be highly appreciated!


Allso, many of the options in ControlSpace are grayed out, for example that the display is set to DIM. I guess this is why the display doesn't show anything.? How do I activate the grayed out options?




Hi Kimmydoo,


"ICV not OK" is not a firmware related issue. It's related to a power supply failure.

However, you can try recovery mode as a failsafe. To do this, you will need a PC with ControlSpace available. Steps:

  1. Turn the amp off.
  2. Press and hold the first, third and last of the 5 buttons below the display.
  3. Turn the amplifier on and wait until "Recovery Mode" appears on the display.
  4. If this stays in this mode, connect a USB cable to your PC running ControlSpace Designer. It will prompt you to force a firmware update due to 'corrupt firmware' (may or may not be corrupt)

If this does not solve the problem, you will want to reach out for service in your region. 


Thank you,




I got my amp working again after also replacing the TI UCC28070 PFC Controller on the power supply daughter board as well as fixing a blown transformer winding on TR4. Schematics would have been nice though.



Hello Marcio,

I've asked our Sales Engineer for Brasil to contact you.