Kicker KX1200.1 Issues

[Dacia Sandero]

Hey guys, I searched through a few threads here and couldn't find exactly what I was looking for, so I registered and figured maybe someone would be able to help me.

I want to start with a disclaimer: I now realize how stupid I was with the set-up I was running, but if you want to call me an idiot, I completely understand!

Now that I've got that out of the way , the set-up I am referring to pretty much brought my Saab's electrical system down to it's knees. I had replaced my Alpine 350W amp powering my single 12" Type-R 4 ohm, with this glorious monster that is the KX1200.1. All was well for a month or so until my car would not start on occasion and needed to be jumped (curious at this point towards the amplifier, but not sure). Then eventually my amplifier would cut on and off, pushing my subwoofer out as if it was slowly filling the box with air, then making a popping noise, repeating itself every 5 seconds or so.

Looking back, I know what my issue was now, but was too stupid to think it was an issue in the beginning. I was running the same 8 gauge wire with a 60 amp in-line fuse that I had ran with the Alpine, and well, basic electricity principles tell me that the wire size I was running was far too small, and the amp was essentially trying to "draw lots of power through a very small straw", as my friend put it.

Now the amp just continues to pop the subwoofer repeatedly. I'm not entirely sure what to do next, but I've got the amp apart right now (green board FYI, not the red one) and don't see anything visually blown, but I've also got a few buddies studying EE here at school with me that are decent with a DMM and may be able to help me out. I was wondering if anyone could point me in the right direction as to where to start looking for problems. Any particular componant you guys know would fry given the circumstances I described? All help is much appreciated!

TL;DR - I ran too small of a wire gauge for my KX1200.1, and now am getting on/off issues with subwoofer popping.

[brandes.cm]

How long of run of 8awg wire? I ran an AQ2200 off 8 awg everyday without issue.

Remove the subwoofer from the output and check the output fets for shorts. Post a pic would be helpful as well.

[Dacia Sandero]

It was approximately a 12 foot run of the 8 awg.

I've got the amp on my desk right now so I can snap some pictures, but without a multimeter and PSU I'm unable to test anything at the moment.

Here are some pics I took with my cell phone:







thanks for the quick reply!

[Perry Babin]

If there are no shorted output transistors, I'd guess that U508 has failed.

There may be another problem. I think (not sure) that this amp has DC offset protection. When there's DC on the speaker terminals, the relay will not stay engaged to prevent damaging the speakers. Repairing the DC offset may not be difficult but without a schematic, finding the reason that the DC offset protection isn't working (or determining if it has DC offset protection) may be a bit more difficult.

[Dacia Sandero]

Originally Posted by Perry Babin

If there are no shorted output transistors, I'd guess that U508 has failed.

Here's a pic of the U508, I don't know if it helps, but it certainly seems a little cloudier in that area (could just be dust?)

There may be another problem. I think (not sure) that this amp has DC offset protection. When there's DC on the speaker terminals, the relay will not stay engaged to prevent damaging the speakers. Repairing the DC offset may not be difficult but without a schematic, finding the reason that the DC offset protection isn't working (or determining if it has DC offset protection) may be a bit more difficult.

I certainly hope it isn't this, as I would not even know where to begin to go about testing that situation, especially when I'm assuming a schematic isn't exactly the easiest thing to get a hold of?

Thank you for your clearly well-informed response, I saw your name pop up a few times in my searches, and people said you wrote a tutorial on repairing these things? I couldn't find it anywhere, but it definitely sounds like you are a go to guy around here for amp repair info, especially this amp in particular.

[Perry Babin]

If you intend to repair this yourself, you should read the basic repair page. It doesn't have any information on this amp specifically but it has basic information that you need to know to avoid many of the most common mistakes.

The link to it is in the sig line below.

[brandes.cm]

If you think this gets to be over your head, kicker offers reasonable repair service.

sent from an IRFZ48N

[Dacia Sandero]

Originally Posted by Perry Babin

If you intend to repair this yourself, you should read the basic repair page. It doesn't have any information on this amp specifically but it has basic information that you need to know to avoid many of the most common mistakes.

The link to it is in the sig line below.

Thank you Perry, that will make for some good reading today. I do not intend to do any serious repairs myself, I plan to take the information you helpful bunch have given me and relay it over to some friends of mine who are a few weeks from graduating with an Electrical Engineering degree (who are also much more well-versed in this than my Mechanical Engineering background allows).

Originally Posted by brandes.cm

If you think this gets to be over your head, kicker offers reasonable repair service.

sent from an IRFZ48N

Thank you brandes, I have read on this site that there is a flat rate for diagnostics of $45, plus whatever repairing costs for Kicker? I actually live very close to United Radio, perhaps if things do get to over mine and my cohorts' heads, I could bring it there for some slight cost savings (not having to ship)?

[peppy6582]

Could any of you guys tell me what the part number for U12 is?

[Perry Babin]

mc14060bd

They rarely fail.

If you have any more questions, start a new thread.