the diode is across the relay coil and will not check like a typical diode. your seeing the resistance of the coil and the diode is okay. with the DC volt test you should see the battery term voltage (whatever your supply voltage happens to be-somewhere around 12 volts) on one side of the diode. Before jumpering the remote terminal, the other side of the diode will read approx 12 volts. the relay coil has no potential difference across it and is not energized and the relay contacts are open. when you jumper the remote terminal and after the amp powers up the voltage to one side of the diode will drop to near zero with the other side of diode at 12 volts. the coil will now see 12 volts and energize, causing the contacts to close.
If you don't see the voltage drop to zero on one side the relay turn on circuit is bad or there's a break in the trace to the relay coil and diode. if the relay has the proper voltage, (you can check this another way by putting the voltmeter probes on either side of the diode and you should see 12volts) and your not getting output, you may have a bad solder joint or the relay contacts are pitted and corroded and not making good contact.
do you have a speaker lying around you can use to test with, if so tie one speaker lead to the neg speaker terminal and the other speaker lead can be used like a voltmeter probe. inject 40 hz and probe first the pos speaker terminal. starting with the gain turned down and slowly turn up the gain.No sound right! well, we new that, I quess! now move probe the the same side of the coil you used to test AC test and again turn gain up slowly. careful not blow the spkr out and don't use less than 4 ohms. what's the result?
I just left for work and will be back home in about 6 hours. short day today 
So I will be back with you as soon as I get home...
now speakers. I have two here I have a Kicker CVR lying around in here and a old Panasonic PA 8ohm very low watts don't remember.
should I just use the subwoofer since it is 40hz range and hold the watts? Just I think its dual 4 ohm so would 8 ohms be okay to use?
So I will be back with you as soon as I get home...
now speakers. I have two here I have a Kicker CVR lying around in here and a old Panasonic PA 8ohm very low watts don't remember.
should I just use the subwoofer since it is 40hz range and hold the watts? Just I think its dual 4 ohm so would 8 ohms be okay to use?
Okay I was a little confused at what you were trying to get me to do and had to reread your message many of times.
But I'm sure you knew exactly what was going to happen.
you was right connect to the speaker pos output I got absolutely no sound
as soon as I touched it to the coil I had a 40hz tone coming from my sub and would get louder as gain is increased.
Seems like we are getting close
But I'm sure you knew exactly what was going to happen.
you was right connect to the speaker pos output I got absolutely no sound
as soon as I touched it to the coil I had a 40hz tone coming from my sub and would get louder as gain is increased.
Seems like we are getting close
Right,your spkr test proved that the amp itself is working and the audio needs to cross that last bridge (relay) to make it to the outside world (spkr term). From the DC volt test results it looks like the voltage from the Power terminal is not getting to the diodes anode (non striped side,the cathode is the striped side). Check continuity/diode check from the power terminal to the diodes anode and cathode.If my guess is right you will not have continuity on either side. Which will prove my point.If that's the case you will need to remove board from chassis and and trace the trace (sorry) with the continuity or ohmmeter. This will be tricky and take some time being that this is a double sided board.The trace runs on both side of the board and is connected by a series of via's(you will recognize them as tiny dots of solder connected to a trace running in one direction and the other side of board will have a trace connected to same via running in the opposite direction). I know I get a little wordy but you will get it!
I noticed signs of moisture near the power terminal, I will send a doctored pic of your board showing what I mean. The corrosion will eat away at traces and via's. I think that's what happened here.But never fear it's shouldn't be that bad. The tricky part will be finding the trace or via.One thing you do is to jumper a wire from the power terminal to the diodes anode, and power up the amp,you should hear the relay click on. You can do an AC test with 40 hz tone. If the amp is outside of chassis DO NOT USE A SPEAKER!! use the AC meter. Amps don't like to be loaded without a heatsink. Okay, I'll shut up now!:0)
http://i963.photobucket.com/albums/ae119/Mrpapazbill/Powerterminals_zpsffac3e92.jpg
You note the moisture around the power terminal. There will be other spots most likely where a via that carry's the 12 volts from battery to the diode.Typically you will find moisture underneath the relay or power transformer. You may want to remove the relay at some point to check underneath it.But will take it a step at a time.
You note the moisture around the power terminal. There will be other spots most likely where a via that carry's the 12 volts from battery to the diode.Typically you will find moisture underneath the relay or power transformer. You may want to remove the relay at some point to check underneath it.But will take it a step at a time.
Okay I cant say I did every single trace but I stoped as soon as I messed something up and idk what yet, but I amp is drawing more power now after one of my probes touched two pins of a transistor together.
It was one of the 4 standing up I believe one of the two closer to the speaker output. but after I did amp went into protect and when came back on I can head the power supply working harder than when pushing a 40hz sound through it
but these are the traces I noticed before that happened.
Red Probe in Power and Black probe put to trace lead points set to DC
Trace Beside C175 I belive had 5 points on bottom all read -.02
Taces on tope though read -12
Trace below C173 that goes to the tall screw base for xboard
On bottom and top of board both read 0
Trace left of R01 top of board read -12 bottom read 0
It was one of the 4 standing up I believe one of the two closer to the speaker output. but after I did amp went into protect and when came back on I can head the power supply working harder than when pushing a 40hz sound through it
but these are the traces I noticed before that happened.
Red Probe in Power and Black probe put to trace lead points set to DC
Trace Beside C175 I belive had 5 points on bottom all read -.02
Taces on tope though read -12
Trace below C173 that goes to the tall screw base for xboard
On bottom and top of board both read 0
Trace left of R01 top of board read -12 bottom read 0
Maybe it's too late, but you shouldn't check the traces with the amp powered on! That's why your meter is giving negative values.
It is possible that you have broken something by connecting two transistor pins with your test probe. Redo your mosfet check (what you did in post #17). Amp powered off
PS: Also, I'm not an expert but I've read the entire topic, I think it's wonderful that PapaZBill is helping you this much
I know the ones you shorted aren't the output mosfets, but everything in this amp is connected to each other. Doing something wrong at the input can cause damage at the output (theoretically, i don't have the schematic of this amp so i don't know).
IF the amp is drawing a large current without a speaker connected, like you said, then there is something wrong. I always check the output transistors first when something like this happens (in your case, the mosfets). Also, something might be getting very hot (large current = large power dissipation) so be careful.
I think it is best to wait for PapaZBill, he probably has some ideas of what might have happened.
I think I shorted out the kia 7812api transistor
I was checking all of them and that one is reading loop now
Multi went real high then stayed at 1
The other kia7812pi is reading 14
And I may be wrong I disconnected my amp and the power supply still sounds like its under a load its only a 15amp power supply Idk if I maybe over worked it on this amp
But I also repeated last test where we got sound to be produced and instantly amp kicks off so I think I blew this fet and hopefully that's it
I was checking all of them and that one is reading loop now
Multi went real high then stayed at 1
The other kia7812pi is reading 14
And I may be wrong I disconnected my amp and the power supply still sounds like its under a load its only a 15amp power supply Idk if I maybe over worked it on this amp
But I also repeated last test where we got sound to be produced and instantly amp kicks off so I think I blew this fet and hopefully that's it
The 7812a is the one not working the regular 7812 reads 12 at 200k
Sorry the pi on them kinda confused me didn't know if it was part or the name or not
And I was actually going off by hearing the power supply itself to know when it was working hard, but like I said I ran the power supply connected to nothing at all and it still makes the noise.
So currently Idk how much the amp is pulling or how to check. And no the xboard was not connected at the time I shorted it or while the amp was running and I assumed that it was pulling extra power. But the supply didn't start making the noise until I did pop thay fet
Sorry the pi on them kinda confused me didn't know if it was part or the name or not
And I was actually going off by hearing the power supply itself to know when it was working hard, but like I said I ran the power supply connected to nothing at all and it still makes the noise.
So currently Idk how much the amp is pulling or how to check. And no the xboard was not connected at the time I shorted it or while the amp was running and I assumed that it was pulling extra power. But the supply didn't start making the noise until I did pop thay fet
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