Help confirming a diagnosis

Have you checked the voltages of pins 3,8 - 9 and 11, 14 and 16 of the 8244's?
If you are new to probing IC's, I do suggest tracing the pins to the closest connections to resistors or capacitors to avoid slipping the probe shorting out the IC pins. That capacitor is connected to ground, probably for filtering or decoupling (assumption) so it should not interfere with the voltage getting to its destinations if not installed as they don't pass DC as Perry noted.
The spec sheet will show the voltage ranges
You may need a scope to check pin 1 for the signal unless someone here can give you the relevant voltage for that input.
 

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I got the amp in. It is a Stetsom amp and the power supply section is different so no help there.

That blows but I still really appreciate all the help though.

Have you checked the voltages of pins 3,8 - 9 and 11, 14 and 16 of the 8244's?

No I haven't and to be honest I'm not sure where that would be. As stated before I only have a general idea of what I'm doing, I'm just trying to save a bit on repair and shipping and get it done locally. Going back to the beginning of this thread would I need to worry about takingthe gate Trans off to help prevent shorting of the input? Also is this related to the video I linked earlier in the thread?
 
I feel your amp did at one point pertain to the video but it is not the current issue.
Since your capacitor is not present (post 8) I will assume the amplifier has been on a bench in the past due to a shorted capacitor. This opens the door to other issues for the fact that we do not know what has been replaced or removed for inspection or replacement. There are MANY inferior parts in this world and incorrect procedures can shorten the lifespan of components. The power cycling in post 1 points to this.

If this amp is of high value to you and you feel uncomfortable testing, I would suggest a repair shop since it is so easy to destroy components with a single slip of a probe or harm to yourself from the high voltages present.
If you want to proceed and you haven't already, read Perry's guide, follow his directions and note the warnings. Knowing the risks, we can help you step by step when you are ready.
To note, a class D amplifier is not the easiest to start with.
 
I did take it to a reputable repair place here locally (mainly deals with phones, tvs, home stereos etc) and told them to follow what he said in the video and see if they come to the same conclusion. They said that yes according to the video it would be the same diagnosis. Besides that the amp was bought brand new from tara, regarding the missing cap the solder appears to me that it wasn't done correctly from the factory as the repair place said they didn't do anything besides what was shown in the video. The power cycling was done by me (not sure if that was clear in the post) the reasoning was like most electronics turning it off then on again normally fixes things so at the time that was my best bet. Are you referring to the guide on this post or another?
 
The amp will run without that cap in place. It may have some switching signal noise due to it missing which can potentially lead to other signal issues depending on the intended purpose of the capacitor. I can't remember if it was in parallel to the electrolytic to ground as a bypass cap or not.
Cycling can lead to high current spikes for future reference.
Here is a link to Perry's guide,
bcae1.com - Car Amplifier Repair Tutorial - The Basics
 
Regarding the 8244 this is what I'm looking for correct?
8244 Integrated Circuits - ICs Datasheets | Mouser

Also that cap does have a side that goes to ground haven't checked to see if it's in parallel or not.
I'll take a good read on that and see what I can get from it, thanks for the link though.

To answer this question, study up on this PDF for that driver.
https://www.mouser.com/datasheet/2/368/Si824x-1398024.pdf


Sorry Perry, it looks like I was responding the same time as you on the last post.
 
The output driver ICs generally only fail when the output FETs fail but I don't have any experience with this amp. Don't replace the output driver without knowing that they're defective.

None of the fets are visibly blown.

That is the pre-amp section to the left and the class D drivers to the right. You can think of that section as the signal input processing section up to the driver IC's.

That's what I figured.
 
This is what I've got so far. There's a difference between the 2, not sure if that makes a difference or not. I would've checked the outputs but I wasn't sure on where to reference those so I left them alone for now.
 

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You have to be VERY careful measuring anything on the driver ICs. One slip and you could do very significant damage to the amp. If you wanted to know if you had drive to the outputs, you could place the black multimeter probe on the FET source leg and the red probe on the FET gate (again, careful not to slip).

I found some components near by that were connected to those legs so I wasn't trying to probe the actual ic as I don't have steady enough hands to do that and they're way to close for comfort. I'll check at the fets for the output here shortly.
 
Well the rabbit hole gets deeper... I'm seriously starting to think this thing wasn't flowed right from the factory. The first pic shows a missing resistor in line with the gate of the fet that isn't showing any life. The second shows the voltages I got across them, I hope the 12v is a result of the other not being in line but idk. Even if I did send it off to get fixed at this point I'd be more worried about other components falling off due to failed solder.
 

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