My dear VSA-D8EX decided it was time to stop working and few seconds after turning on (with the usual power relay click), it clicked a second time and went straight back to standby (power LED on = red).
It's 19 years old, and if we count life of A/V amps like the life of cats, it's a very, very old grand daddy. If I spread its initial cost over 19*12 months, it cost me something like $8/month. A pretty great deal in the end, thank you Pioneer.
Taking it to professional repair would be pointless: a used one can be found easily for for $50 on YAJ. Repairing it would cost far more than $50.
It's time for a long overdue upgrade. Not completely a surprise as I have been planning for this little guy's death for years now and the plan B is already in motion.
But, still, if I'm going to trash it, I might as well try to fix it myself or at least give it a little resurrection for a few more days/weeks.
Plastic turned yellow. Painted cover peeled. Dust and some light corrosion. It's dirty.
The top-left part is where the standy/power button on the front goes back to the power board next to the power plug cable. One of the 3 relays (2 blue, 1 black) is the one doing all the clicking but I can't tell which. It seems that it detects a shortcut or something weird and does its job of self-preservation.
The fuse isn't blown.
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Googling around for Pioneer power/standby/clock issues only bring very recent models for which there is some software reset you can perform on the front buttons. Not on this model.
Test recommended was to power off, unplug power, unplug every external connection (speaker, audio, etc.) and plug power + turn on. This is to remove any chance of short-circuit coming from an outside device.
That didn't change anything. So trouble is internal.
Since the power board won't power up, I can't test with a multi-meter. There's nothing to test.
That's why I'm opening up to the wisdom of the forum: what would be your next troubleshooting step?
Hate to say it while I don't know it could actually be the power switch, if its one of those soft touch ones they do go bad.
My Carver amp has an issue with the power switch and relay inside, never opened it up and just have it plugged into a switch on the side that I can power on and off.
My issue was the relay would get stuck on and never be able to turn off until the caps would drain.
Hate to say it while I don't know it could actually be the power switch, if its one of those soft touch ones they do go bad.
It does recognize external power (Standby LED goes red). When I use the Standby/ON button to turn it full on, it clicks normally.
I can hear the soft buzz of the transformer doing its job for half a second and nearly instantly it clicks back to Standby. The LED display panel never wakes up and remains dark.
The fact that it initially turns on but then quickly shuts down again might indicate a protect mode. However, some amps will tell you that in the display. Can you confirm if the manual would state this if it would occur. If not, might need to look into the possibility that one of the seven power amp transistors now has a short that’s keeping the unit off.
Possibly another issue is in the standby power supply where it just won’t allow the unit to initialize. My Marantz that I have has two blown resistors that might be the only reason I can’t power it up.
Last edited by ldfan on 17 Sep 2020, 23:02, edited 1 time in total.
I don't know as much of these newer electronics with switches that turn on other internal switches to relays etc.
my only guess is that its something past the switch, but ldfan sounds more like the right solution, something making it shut off. but my guess is that its something bad from wear to make the next piece not turn on or keep it on.
I was sold a Harman/Kardon AVR 75 that would not power on. The solution was a firm slap to the side of the unit which I guess was all the relay needed.
I see ~104V reach the power board and go through the fuse. Then they go through a relay activated by the Standby/Power ON button before reaching the inputs of the transformer.
When clicking I see briefly the voltage rising but the relay clicks back and the voltage goes to 0 again.
That's as far as I can go: yellow gets the right voltage (104.5V) but the relay in red refuses to engage.
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It could be the Standby Button that's not keeping voltage anymore (towards the end it was getting increasingly hard to push correctly to turn the amp on) but getting to that part would require a major disassembling job.
At least I didn't burn anything or got a power shock. Quite a few places when you could touch unprotected 100V contacts.
I still don’t know enough about electronics so not sure if a power button even gets any power or is it just sending a signal (I would think the latter since the button plays no part when using the remote to turn it on).
In any case, if you could remove the “standby” power supply from the unit and just go over it with a voltmeter looking for shorts (unplug from power), you might find something that could be affecting it.
Here is a video from 12voltvids that I found pretty useful that could help....
Wondering if AC3RF is a separate board that could be recycled...
In most or maybe all cases, it's probably integrated into the digital input board. Thus, it would be hard find a way to recycle it into something like a standalone box since it would need support circuitry to run it.
In any case, I hope you do find the issue and get it repaired. It would be a shame to let something like this go considering how I dislike the build quality of today's AV Receivers. If I had to upgrade @ this point (and if money was not a limitation), I could only see myself building a new system based on a Pre/Pro + outboard multi-channel amp.
Anyway... just to give another hint about power supply repair. Recently, one of my Mitsubishi VCRs' just suddenly died so I decided this might be a fun project to see if I could find the issue. After poking around starting from the AC cord, then to the power transformer, and finally to the power supply stages; I found the problem to be a totally shorted 50V transistor (all three legs making continuity). I have the part on order and hopefully it's the only thing I will need to repair it (everything around it appears to be fine). If that ends up being the case, total cost will be about $6.
Adendum as of 9/27/2020 >>>> Well, the transistor in my VCR was a major portion of the issue. The unit powers up as it should again but after 30 min of testing something happened and now I get a distorted pic and sometimes muted audio on playback (linear audio; no HiFi on this model). Looking to see if caps adjacent to the transistor might have been overloaded and see about replacing.
Last edited by ldfan on 13 Oct 2020, 04:39, edited 2 times in total.
If I had to upgrade @ this point (and if money was not a limitation), I could only see myself building a new system based on a Pre/Pro + outboard multi-channel amp.
I reached the same conclusion given how poor the offer for integrated (and even non-integrated) market for multichannel was in Japan today.
You are down to Marantz or Yamaha for mid-range, and very few models to chose from. Or you need to look up at the higher range.
Decided to sell one kidney and invest for the next 20 years!
But the replacement units won't be delivered before end of October or early November at earliest.
Sometimes the pins on the relay oxidize over time so when they close it doesnt make a connection. Had an old Akai amp that had that issue. Cleaning the contacts on the relay was a temporary fix. In the end I had to replace it wholesale.
Decided to sell one kidney and invest for the next 20 years! But the replacement units won't be delivered before end of October or early November at earliest.
That one will last presumably a LOT longer than the Pioneer!
Will keep trying to fix the Pioneer for fun. Can't get worse now anyway. If Onkyo (ex-Pioneer A/V) has an outlet somewhere nearby in Tokyo I might have it checked for a quote and use it in another room.
Looks promising. I think it probably is in "protect mode" but the service manual or a general search on the web can tell you. If so, shouldn't be a difficult fix .
My Marantz NR1605 is turning out to be a bigger headache. At first I thought it was damaged in a power surge but I'm now finding that the standby power supply is checking out fine. I'm pretty sure it's not in protect mode but I'll have to pull the amp section out to test the seven amplifier transistors. If that is not it, maybe a bad relay or something else on the main power supply . In any case, I'm hoping it's not the CPU because @ that point the unit is bricked .
Looks promising. I think it probably is in "protect mode" but the service manual or a general search on the web can tell you. If so, shouldn't be a difficult fix .
Well, the person who submitted the video of the black Pioneer VSX-909RDS (very similar model), told me fixed it by replacing the regulator board.
Based on close Service Manuals (VSX-908RDS, VSA-E07 and SA-E08), it's either:
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. In any case, I'm hoping it's not the CPU because @ that point the unit is bricked 
.
