Kicker ZX750.1 Shutting down at high volume

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I am having an issue with this Kicker Amp,

The complaint is that the amp was cycling in/out of protection at high volume. (35-40 amp draw)

I am able to confirm this by looking pulse for shut down, out of Pin 13 of U02 (KIA339).

My theory is that that comparator monitors the 12v incoming line and turn off if its to low.

PapaZ , can you confirm?
 
I will have to look at schematics and that won't be until Monday.I believe that's right but will need to look at the circuit to refresh my memory about this amp. It's been some time since I've work on this one.

In the meantime post pics of amp.

Also, check the DC voltages around the LM361 and waveforms on Pin 4,9 and 11 and list readings and post screenshots. Check DC voltages from Source to Gate on the IRF640's and IRF9640's and check the drive waveform to the Gates and output inductors. You will only need to check one output devices for each bank.

It's not necessary to attach a load or apply audio or test tone. I just won't to see the idle conditions. You may need to remove the preamp board.
 
Here is the information you requested,

Lm 361

4: .04
9: .09
11 :56

Attached are the images you requested.

Note the capacitors that appeared overheated. I did replace them. It appears that it may have corrected the problem. But I am unsure, as I need to test more.
 

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  • Vented.jpg
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Looking at your last post, the Class D circuit appears to be working.

If the caps you pulled are vented as you say, replacing them may have fixed the issue. Which caps did you replace?

The KIA339 is the looking at B+ and shuts down the TL494 when there is a overvoltage,undervoltage or thermal event.
In this case undervoltage protection.
 
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