Ok, so I have a pioneer surround sound that I was trying to fix because of one speaker had very low volume on SBL speaker. The first thing that I did was changing a resistor on that speaker, it had the same color stripes, the size was only a bit bigger. When tested, the surround sound detected an error and went into protected mode, and I forced reset and shorted two bridge rectifiers and I replaced them and I changed the resistor to the correct one. After inspecting more thorougly, I found IC501 (input volume selector) and pin 28 was a kind of black and it is the input for SBL. So I cleaned with alcohol and resoldered for better connection and also replaced the capacitor that goes to that pin. Then, I turned it on and it turned on without an error message for just a couple of seconds and turned off to protected mode. I forced reset it one more time and this time I do not have volume at all on all speakers. Could IC501 be shorted or faulty? Can someone help me troubleshoot, I am a beginner at troubleshooting and do have function generator and oscilloscope if needed.
Update: I figured out I had the a couple of cards and sound card loose. The first one I seated is CN501, maybe the problem is here? I seated correctly and turned on for a couple seconds and turned off into protected mode.
Schematics manual: Pioneer-VSX-1017TXV-K-Service-Manual
Update: I figured out I had the a couple of cards and sound card loose. The first one I seated is CN501, maybe the problem is here? I seated correctly and turned on for a couple seconds and turned off into protected mode.
Schematics manual: Pioneer-VSX-1017TXV-K-Service-Manual
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Ok, so how could I find the problem? I would also like to mention that I had just realized on the schematics the exclamation point means it has to be the same type and specs. When I changed R3061, I used wrong type and 2 bridge rectifiers blew up, but I do not know what else is the problem, the system turns on fine for a couple of seconds and shuts down to protected mode. On page 172, the 2 bridge rectifiers that blew up is D3301 and D3302. Also on page 112, it should say D5SBA60 and not D5SBA20. Can someone guide me on what to look for? The system was working before, just SBL speaker was low on volume.
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The amplifier could care less about what type of resistor is in that location, the warning is a safety issue, probably Flame Proof. The only reason for that resistor to go bad is the choke/inductor in parallel with it has a bad connection/solder joint. 99.9% of the signal goes thru the inductor so if the inductor is out of the circuit the signal must pass thru the resistor which obviously it's not nearly large enough for that. How you can blow up the bridges without blowing the line fuses is beyond me. Are you sure they are bad? In or out of circuit? If in circuit you'll need to keep your meter on for several seconds in order to charge up the filter capacitors until then they'll look like a short.
Craig
Craig
Ok, when I suspected they blew up was because I saw smoke coming out from that area, at first I did thought it was the fuse but it was not. There was silicone that came out of the bridge rectifiers. When you ask "In or out of Circuit", I assume you are asking if the bridge rectifier is on another board separated from the board that I changed the resistor, in that case yes. What would be the purpose of charging up the filter capacitors?
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When you check bridge rectifiers that are still in the circuit, ie connected to the filter capacitors, the voltage from your meter will charge up the capacitors and will look like a short circuit for a few seconds then you will see the reading start to go up. If the recifiers are truly shorted there will be no change in the reading.
Craig
Craig
I dont think I mentioned that I did replace those 2 bridge rectifiers before I tried to turn on again. The symptoms I am having is after I change those 2. No power with the old bridge rectifiers. Sorry about that. But you do want me to test out of circuit? I can try.
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Looks like I do not have continuity from IC781 PIN 1 to C789 positive side. There is continuity from C789 positive side to R797. I posted pic on 1st post or you can go to page 87.
Ok so I test in diode mode and ohms mode and compare it to a good one and the readings are just about the same. So possibly still good? I posted video in ohms but did not show diode mode in video.
Ok, I had a couple of open issues with capacitor and loose cards, I manage to fix it as much as I can and I apoligize for having these issues I did not mention. Now my problem is that it is restarting after it loads Advanced Surround Sound Mode. I hope I can solve this issue.
Ok, I dont know how I finally got my amplifier to stop restarting but it remained on for some reason. I tested each speaker channel with radio antenna connected and it just makes distortion noise. So I thought maybe is not sending good audio signal from antenna and I pushed the connector on CN601 near an audio codec chip? And the problem reoccured, it keeps turning on and off. What could be my problem?
Ok, I have an update I figured out that IC701 was bad because when card of this IC chip is off the system does not turn off again. So I changed and I tested and the input buttons were all lighted orange, and only one input selected should be orange. So I figured out that Input Selector and Volume (IC501) may be bad and I replaced and now one input selected is lighted correctly. Now another problem, when I connect speaker to SBL, the speaker makes a loud pop sound and turns off immediatly. I disconnected speaker and plugged to FL instead and it does not turn off anymore, I just hear small beeps. However, I went into speaker test in the options and turned off instantly. Perhaps at this point IC781 SBL transistor is bad? Its the only thing I haven't changed.
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