Repairing QSC 12.2 Active Loudspeaker for Power supply problem in SMPS Board....Most uncommon Fault.

Repairing QSC 12.2 Active Loudspeaker for Power supply problem in SMPS Board, found the issue very rarely this type of fault is happening.
Very very tricky & tips of volt test.
Most uncommon Fault....
#qsc12.2activespeakerpowerproblemsolved
#repairingqsc12.2activespeaker
#qsc12.2activespeakerrepairedpowerproblem

[@sekaraudiojolarpet7232]

Ur rocking

[@jesuscolunga2281]

Saludos! Por favor información sobre JBL PRX800.

[@TKFElectronics]

What information you need & how can I help you bro

[@ejazshahelectronicsrapring1704]

🌹

[@samuellarbie1014]

Boss thank you your video help me a lot

[@TKFElectronics]

Welcome bro

[@izzzzzz6]

With power flashing screen on and off I think it is: D51 (an smd SL110 and possible Q23 a small 6 pin device near D51) Looks like the frequency driver for Q13 and Q14 I'm getting 23 ohms both directions across D51 and 0.040 in diode mode on my meter. To be honest i will probably put this back together and let the warranty centre take care of this. I will probably rent a speaker to the guy because it will take time to order these components and he will probably only save 2 weeks. But on the other hand i'm a little concerned about renting speakers that are going to be used on a mountain at 2600M! Actually the diode is marked KB whick seems to be a zener KDZ4.7B. The 6 pin smd is printer 001N but i do not know what this device is it might be ok.

[@izzzzzz6]

I'm about to open one of these. No idea what's wrong with it. He has it at 2,600M on a mountain and he thinks it got water inside. It's still under warranty but the same thing already happened to the other one and he doesn't want to send this one to Thomann because the last one took one month to repair and he thinks they said it was just an internal fuse. He said it lights up though. Let me see. Right. So, it powers up and everything looks normal on the power led and the screen but after 3 seconds it shuts itself down and immediately starts up again for 3 seconds and so on.

[@izzzzzz6]

Update. I found some information. D51 is supposed to be a RB751S40T1 Schottky. However the diode in there was marked KB which is a type of zener. Confused still as to why / how this can happen. Since this QSC asked an independent technician to call me and the owner will now decide if he can get an entire module at around €400 sent by this technician under the cover of QSC or not. If not i will continue with the repair.

[@djxoy6]

where can I buy ic parts online for this speaker

[@toddwhite7144]

HI, any solutions on why QSC k12.2 powers off. Reboot and it works. I sent off in 2020 to be fixed. it took over a year. Now back the issue has happened 4 times.

[@TKFElectronics]

Main motherboard issue, may be system ic malfunctioning

[@prakashrabha5473]

Sir nx audio active speaker mosfet burn. I changed mosfet 20 n50 n ir2153 ic but power supply not work

[@TKFElectronics]

Check some other electronic components around ic & MOSFET

[@DDEVAOfficial]

Hi where you from ?

[@TKFElectronics]

Mumbai & our contact no. [phone]

[@harishchandrasingh8074]

Sir QSC K 12.2 ka RMS watt at 4 Ohm & 8 Ohm kitna ata hai... Please reply 🙏🙏🙏

[@suryakantabarik1856]

2oms

[@abdyjeff]

I have QSC KW 181. The power is there, but there's no signal... That makes it not to produce the output to the speakers. what could be the problem

[@TKFElectronics]

May be Amplifier board or pre amp circuit

[@abdyjeff]

@@TKFElectronics thanks for your reply. Have checked it, and it's the pre amp which does not function. And I don't know how to fix it

[@TKFElectronics]

Your location

[@TKFElectronics]

If you r not technically qualified person, i suggest you pls visit your nearest QSC service center

[@abhinanhamangli3266]

Sir muje ye modul cahiye kaha se milega

[@TKFElectronics]

Contact QSC service center

[@mgarcia12]

my qsc k12.2 power supply light keeps on and off... any initial assessment on the problem?

[@TKFElectronics]

May be problem will be in Power supply section or Amp Board

[@izzzzzz6]

Hi. Did you fix it? I have the same issue.

[@TKFElectronics]

Very simple bro by replacing defective parts with new

[@izzzzzz6]

/@@TKFElectronics I'm inside. Not the easiest to dismantle! (still under warranty but the 1st speaker took one month for them to repair) About to remove PSU board now. On the smaller filter circuit there is a green ceramic capacitor? In a plastic holder on the side of the small board between two large inductors. It is showing 13 ohms. is this ok? I feel like the issue must be further up in the PSU. I'll post back if i find the problem. Update. The green ceramic is NTC inrush filter R41 and can sometimes be broken but not in this case.

[@izzzzzz6]

@@TKFElectronics I think it is D51 (an smd SL110 and possible Q23 a small 6 pin device near D51) Looks like the frequency driver for Q13 and Q14 I'm getting 23 ohms both directions across D51 and 0.040 in diode mode on my meter. To be honest i will probably put this back together and let the warranty centre take care of this. I will probably rent a speaker to the guy because it will take time to order these components and he will probably only save 2 weeks. But on the other hand i'm a little concerned about renting speakers that are going to be used on a mountain at 2600M! Actually the diode is marked KB whick seems to be a zener KDZ4.7B. The 6 pin smd is printer 001N but i do not know what this device is it might be ok. Now i'm not sure what the diode D51 or XB is because the code XB shows and different types of diodes and I can not find the schematics on the QSC site.

[@suryakantabarik1856]

Address

[@sksoundnikhilpatel5232]

Hello sir.... K12,2 same problem.. pliz sand contact number. Or Address..

[@TKFElectronics]

Contact no. [phone]

[@TKFElectronics]

What's app me on this mobile no. [phone] & i will send you my address