Amplifier Not Turning On

[AnthrAxNSB]

I was in a car accident a few weeks ago. When the accident occured (at 35 mph on my front end), my amplifier turned off.
I assumed it was a blown fuse.
However, today I checked for power at the amplifier and I was seeing 12 volts at the "Battery" 12v constant power terminal and 12 volts at the "Remote" terminal. For kicks, I checked the fuses on the amplifer anyway, and they both had continuity.

I'm certain it is a power issue, though (that the amplifier isn't turning on) because the light that displays when the amplifier is powering up is not turning on and, of course, the subs aren't playing.

Any ideas about what could have happened and how I can troubleshoot?

BTW: The amplifier is a Kenwood KAC-829 600w 2 channel

[Notladstyle]

I was in a car accident a few weeks ago. When the accident occured (at 35 mph on my front end), my amplifier turned off.
I assumed it was a blown fuse.
However, today I checked for power at the amplifier and I was seeing 12 volts at the "Battery" 12v constant power terminal and 12 volts at the "Remote" terminal. For kicks, I checked the fuses on the amplifer anyway, and they both had continuity.

I'm certain it is a power issue, though (that the amplifier isn't turning on) because the light that displays when the amplifier is powering up is not turning on and, of course, the subs aren't playing.

Any ideas about what could have happened and how I can troubleshoot?

BTW: The amplifier is a Kenwood KAC-829 600w 2 channel

ground the power cable for a second at the amp, tap +12v against the gnd and make sure you get lots of sparks. the amp contains capacitors that could hold 12v even if the source wasnt supplying.

[AnthrAxNSB]

...done.

The inline fuse is good. When I probe the power cable or remote cable and ground cable, there's 12v.

[Notladstyle]

...done.

The inline fuse is good. When I probe the power cable or remote cable and ground cable, there's 12v.


did you probe it when it was not connected to the amp?

after that disconnect the radio turn on lead and run a wire from +12v to remote on and see if it turns on.

[AnthrAxNSB]

I tested the wires when they were disconnected from amplifier.

I've already bridged the 12v and remote terminals (I took the amplifier out of the car and bench tested it in the house) and it still did not power up.

I'm 100% positive that the amplifier does not power up when it receives 12v to 12v constant and 12v remote. There is no problem with power getting to the amplifier. It is just that it does not power up despite receiving power.

What could have happened on the board; in other words, what would have blown between the 12v terminals and the "power up light" that I'm going to be able to test?

[TBSpyder]

Seems simple enough to me...your amp is fucked. Are you trying to repair the amp yourself or what?

[AnthrAxNSB]

Yes. I assumed somebody in this section is an expert of sorts and would be able to assist me in troubleshooting. I also thought somebody might have some insight on what could have possibly happened during the accident that caused the amp to get "f*cked."

[TBSpyder]

Yes. I assumed somebody in this section is an expert of sorts and would be able to assist me in troubleshooting. I also thought somebody might have some insight on what could have possibly happened during the accident that caused the amp to get "f*cked."

Probably not, if you've ever opened up an amp, you'd find a large circuit board filled with all different size transistors, resistors, capacitors, etc.. Number one, it'd be rather difficult to pinpoint the problem considering you usually cannot just "see" a problem in a circuit board, especially without having the technical schematics of the amp to reference. And number two, once the problem was found, there's a good chance you're not even going to be able to find the exact replacement part.

[GradeA_TireFryer]

Seems simple enough to me...your amp is fucked. Are you trying to repair the amp yourself or what?

:-o :roll:

[AnthrAxNSB]

:-o :roll:

No sh*t!

Perhaps I should have titled the thread, "My Amp is F*cked." It would have gotten straight to the point and expedited the process of learning no one here (who's willing to post) knows sh*t about repairing amplifiers.

[93ex]

No sh*t!

Perhaps I should have titled the thread, "My Amp is F*cked." It would have gotten straight to the point and expedited the process of learning know one here (who's willing to post) knows sh*t about repairing amplifiers.


Maybe asking about repairing an amp instead? Dont get pissy when you ask a roudabout question and dont get the answer?

Hey guys my speakers wont work?


Oh yeah I knew they were all blown but I wanted to know what size they were to replace them.

[AnthrAxNSB]

Any ideas about what could have happened and how I can troubleshoot?

What could have happened on the board; in other words, what would have blown between the 12v terminals and the "power up light" that I'm going to be able to test?


These were the questions.

There's nothing roundabout about them.

The responses were all to make sure I was getting power to the amplifier, rather than to explain what might have happened during the accident to cause the amplifier to get "f*cked" and how I can test for the broken component.

This:
[...] My speakers won't work[.] Oh yeah I knew they were all blown but I wanted to know what size they were to replace them.

is not analogous to the questions I asked.

[TBSpyder]

Yeah, well sorry...there's not too many electrical engineers that frequent the boards who are willing to troubleshoot some kid's Kenwood amp. Doubt any of these company's service departments would be charging outrageous repair prices if it was that easy. If you find someone though, please share with the rest of the community...because if you would have done a search you'd find that similar questions have been asked a million times before.

[Notladstyle]

These were the questions.

There's nothing roundabout about them.

The responses were all to make sure I was getting power to the amplifier, rather than to explain what might have happened during the accident to cause the amplifier to get "f*cked" and how I can test for the broken component.

This:


is not analogous to the questions I asked.

Its possible to repair but its not a swap the fuse out type job. you need a board solder and access to proprietary parts.

If you want to ensure that the problem is the turn on circuit, first check the outer power fuses, then open it up and trace the remote lead until it reaches a small black chip. That chip will have several outputs that check for protect mode conditions before sending power to the transistors that supply power to the amp circutry.

Check that you have power at the lead that supplies power to the circuit.
Check that there is continuity between the RCA points and the 1. parallel resistor across the leads 2. the choke coil(spooled wire around some type or core) and to the RCA plug.

Also check the primary choke coil which is really big copper coil of wire that filters noise from the power line - they vary as to their configuration so I couldnt tell you what to look for.

Ensure there is NOT continuity between the gnd and the RCA leads pos leads.

Back to the turn on circuit:
Check each terminal - there should be one lead that shows 12v to the turn on relay(usually a transistor to prevent noise), the rest should have either no power or consistent voltages as they are protect mode leads.

As you can see its not an easy process to diagnose board problems and this barely scrapes the surface.

Some amps such as newer JL and the kenwood SX amps even have binary turn on signals which cannot be read with a multimeter. Your best bet is to send it in under warranty.

[93ex]

These were the questions.

There's nothing roundabout about them.

The responses were all to make sure I was getting power to the amplifier, rather than to explain what might have happened during the accident to cause the amplifier to get "f*cked" and how I can test for the broken component.


Yeah and instead of coming right out and saying it in the first post, or evenin your first reply, you waited till dalton attempted twice before you mention the board, my mistake. Heaven forbid you ask the question you want answered in the first post.

[AnthrAxNSB]

You all are being dicks.

I asked a question and did not give anyone sh*t about anything. You're b*tching for the sake of b*tching. Nonetheless...

Yeah and instead of coming right out and saying it in the first post, or evenin your first reply, you waited till dalton attempted twice before you mention the board, my mistake.

The FIRST POST I MADE had the FIRST QUESTION I POSED. You're just being an asshole.

The second question was my way of reframing the first question because, despite the seemingly straightforward nature of my original post, it was not clear to the only individual in this thread who has responded to my question directly.

Again, I described the problem accurately and asked the appropriate question. And, again, you're just being an asshole.

Yeah, well sorry...there's not too many electrical engineers that frequent the boards who are willing to troubleshoot some kid's Kenwood amp. Doubt any of these company's service departments would be charging outrageous repair prices if it was that easy. If you find someone though, please share with the rest of the community...because if you would have done a search you'd find that similar questions have been asked a million times before.

I did a search. I did not find an answer to my question. Therefore, I asked the question and hoped that someone on the board might recognize the problem and, possibly, the typical cause.
For example, if someone's car is overheating and pushing fluid from the coolant reservoir, my first suggestion would be to check the radiator cap, because a cap that doesn't seal properly will cause that problem.
I assumed this might be a similar situation in a different context. If it's not, then it's not. Awesome.

People charge outrageous repair prices for mechanical repairs, but I find mechanical work generally quite simple. People have specialized skills that they use to posture their services on others without these skills. Price reflects demand.

Further, I'm not sure what your attitude is about. I've not given you one. I only took umbrage with the " :-o :roll: " comment from GradeA_TireFryer, implying that it was obvious that the amplifier is broken and I should have been aware of that before asking the questions I asked.
I agree it is obvious that amplifier is broken, and my posts reflect that. My questions are, essentially, all things considered, what component within might be broken. So, to the comment " :-o :roll: ," I reply, "No sh*t!"

Thanks, though, to NoTLaDStyle for at least attempting to help me out.

[Notladstyle]

Holy shit man, either you have an awesome vocabulary or you are really good with a thesaurus. sorry about the misunderstanding :D

[AnthrAxNSB]

There's no need to apologize. Apparently I was not describing the situation in an accessible manner. Thanks for you help.

I'm inclined to believe that I probably arced the amplifier somewhere. If the amplifier case made contact with the speaker's +/- terminals, could that burn an internal component without blowing a fuse?

[GradeA_TireFryer]

ok dick, if you want to fix it your self try this http://cgi.ebay.com/Kenwood-KAC-829-Power-Amplifier-Service-Manual_W0QQitemZ5768689675QQcategoryZ39734QQssPage NameZWD1VQQrdZ1QQcmdZViewItem

[AnthrAxNSB]

Thanks. But, my name's not Dick, it's Cory.

[TBSpyder]

:violin:

[Notladstyle]

There's no need to apologize. Apparently I was not describing the situation in an accessible manner. Thanks for you help.

I'm inclined to believe that I probably arced the amplifier somewhere. If the amplifier case made contact with the speaker's +/- terminals, could that burn an internal component without blowing a fuse?

ouch, yes older model amps will melt themselves if the terminals are short circuited after the amp is already powered on. I did that to a couple MTX 202 amps years back while trying to bridge them.

theres good new though! is the terminals were short circuited you can prolly find the damage on the board and possibly repair it/replace the fets.

[AnthrAxNSB]

Cool. I'll have to open it up sometime this week.

[93ex]

:violin:


You need to type much more verbose than that. I can not completley understand the depth of your reply consodering the circumstances present to me at the current point in time. Upon further review I find that That on the first day of January, in the year of our Lord one thousand eight hundred and sixty-three, all persons held as slaves within any State or designated part of a State, the people whereof shall then be in rebellion against the United States, shall be then, thenceforward, and forever free; and the Executive Government of the United States, including the military and naval authority thereof, will recognize and maintain the freedom of such persons, and will do no act or acts to repress such persons, or any of them, in any efforts they may make for their actual freedom. That the Executive will, on the first day of January aforesaid, by proclamation, designate the States and parts of States, if any, in which the people thereof, respectively, shall then be in rebellion against the United States; and the fact that any State, or the people thereof, shall on that day be, in good faith, represented in the Congress of the United States by members chosen thereto at elections wherein a majority of the qualified voters of such State shall have participated, shall, in the absence of strong countervailing testimony, be deemed conclusive evidence that such State, and the people thereof, are not then in rebellion against the United States. Now, therefore I, Abraham Lincoln, President of the United States, by virtue of the power in me vested as Commander-in-Chief, of the Army and Navy of the United States in time of actual armed rebellion against the authority and government of the United States, and as a fit and necessary war measure for suppressing said rebellion, do, on this first day of January, in the year of our Lord one thousand eight hundred and sixty-three, and in accordance with my purpose so to do publicly proclaimed for the full period of one hundred days, from the day first above mentioned, order and designate as the States and parts of States wherein the people thereof respectively, are this day in rebellion against the United States, the following, to wit. So furthermore upon concurrance of my fellow forum members I feel that reviewing the forementioned text was required and almost ceartainly warranted.

[TBSpyder]

You need to type much more verbose than that. I can not completley understand the depth of your reply consodering the circumstances present to me at the current point in time. Upon further review I find that That on the first day of January, in the year of our Lord one thousand eight hundred and sixty-three, all persons held as slaves within any State or designated part of a State, the people whereof shall then be in rebellion against the United States, shall be then, thenceforward, and forever free; and the Executive Government of the United States, including the military and naval authority thereof, will recognize and maintain the freedom of such persons, and will do no act or acts to repress such persons, or any of them, in any efforts they may make for their actual freedom. That the Executive will, on the first day of January aforesaid, by proclamation, designate the States and parts of States, if any, in which the people thereof, respectively, shall then be in rebellion against the United States; and the fact that any State, or the people thereof, shall on that day be, in good faith, represented in the Congress of the United States by members chosen thereto at elections wherein a majority of the qualified voters of such State shall have participated, shall, in the absence of strong countervailing testimony, be deemed conclusive evidence that such State, and the people thereof, are not then in rebellion against the United States. Now, therefore I, Abraham Lincoln, President of the United States, by virtue of the power in me vested as Commander-in-Chief, of the Army and Navy of the United States in time of actual armed rebellion against the authority and government of the United States, and as a fit and necessary war measure for suppressing said rebellion, do, on this first day of January, in the year of our Lord one thousand eight hundred and sixty-three, and in accordance with my purpose so to do publicly proclaimed for the full period of one hundred days, from the day first above mentioned, order and designate as the States and parts of States wherein the people thereof respectively, are this day in rebellion against the United States, the following, to wit. So furthermore upon concurrance of my fellow forum members I feel that reviewing the forementioned text was required and almost ceartainly warranted.

Negatory, could I not have pronounced myself in a more direct and applicable manner? If you would have fully reviewed my previously stated submission, you would have discovered with overwhelming confidence that I was simply asking what issues may have transpired in order for my violin to play in such unacceptable form. Upon further reveiw, you would have discovered that in direct correspondance of this violin mishap...I am displaying a somewhat sad face which should only lead one to the correct assumption that I am rather glum. But, alas, I am to guess this forum lacks such a qualified violin expert to make an assesment on my befallen instrument. I say good day sir.

[93ex]

Negatory, could I not have pronounced myself in a more direct and applicable manner? If you would have fully reviewed my previously stated submission, you would have discovered with overwhelming confidence that I was simply asking what issues may have transpired in order for my violin to play in such unacceptable form. Upon further reveiw, you would have discovered that in direct correspondance of this violin mishap...I am displaying a somewhat sad face which should only lead one to the correct assumption that I am rather glum. But, alas, I am to guess this forum lacks such a qualified violin expert to make an assesment on my befallen instrument. I say good day sir.

Good day.

*puts top hat on*

[TJElite]

Cool. I'll have to open it up sometime this week.

As long as you don't mind voiding any warranty, this is the best bet. I'd also look for some sort of internal fusing...Rockford used to hide a couple of little glass fuses on the board, to protect the amp in case of install screw up. These weren't mentioned in the manual...they wanted the amps brought back to the shop, so they could figure out what you did.

I'd tend to doubt its anything on the output side shorted. In my experience, this causes one or more output devices to go to ground. When this happens, you'll blow every inline fuse you put in, even with the amp turned off.

I'd lean more toward either a broken board, or maybe something like the one of the terminals (power, gnd, remote) having come disconnected internally. Most of the components inside are very light weight, so they wouldn't have enough momentum to break loose. The exceptions are the caps and coils, so you can check those.

Toby

[AnthrAxNSB]

Yeah...

My responses were excessively wordy. Words like "the," "it," and "believe" were simply unecessary.

The violin parody was funny, though.