There seems to be a secret within the VSX-859/839/35
The "unstoppable" VSX-859 automatic "POWER OFF" problem.
The Pioneer VSX 859-RDS / 839-RDS and all equal Receivers (VSX-D859TX, VSX-859TXG, VSX-35TX, VSX-33TX), have an intelliegent error detecting software. The detection is done by the dedicated inputs of the main microcontroller. A number of occuring errors can be detected and catched at dedicated ports by there voltage levels.
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And of course there is a list inside the software, what errors can occure. But there seem to be one or more errors, which are extremely dangerous, that the entire receiver must be "Shut Down".
Die Message ist simple. You switch on the receiver in standby modus with the "power on" pushbutton. It starts to initialize the mainboard and after 3 seconds, after displaying the last function (in our case it's FM with 102.5 MHz), the display changes to "POWER OFF" and the receiver shuts down the power back to it's standby mode.
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So what is the current experience with our samples ?
Cuurently we own 8 odef the VSX 859 and one VSX 839. We got an early one VSX 859RDS - making / smelling a lot of heat after some minutes -, taking about 270 Watts (VA) without any audio-signal. It runs fine with 2 stereo channels, but becomming really hot. So we did take out the Power-Amp block and check the new power consumption. It was low with about 42 Watts (VA). Our other running sample of the VSX 859 consumes 68 Watts (VA) with the connected 5 channel poweramp-block - running fine.
So we know, the total power consumtion of a well working VSX 859 will be between 68 and 74 Watts (VA). If its more, the poweramp-block must be faulty.
And we found out, the entire VSX 859 ist running well without the poweramp-block. The poweramp-block ist not nessecarily important for any error-detection, if its unplugged from all cables.
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Some VSX 859 did arrive with that POWER OFF message
Without any question and any initial check, we did take out the power-amp block, because we did know from others, the VSX 859 will work fine without that power-amp module. - But however, the error ist resistant and it did shut off the receiver after 3 seconds.
Now we have three of these mainbaords, which will no more work - with or without a checked power-amp module.
Ok, a "factory reset" would or will help, was the next idea. But within the total google search engine, no hint or tip was found, how to reset the VSX 859 or its similar brothers.
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The secret : "How to reset the VSX 859" or to initialize the memory with its registers.
In google and other search engines we found a lot of tips and tricks for other Pioneer A/V-receivers, to push the "STANDBY/ON" button together with one of the other buttons of the frontpanel, to receive the "RESET" Question in the display. But non of the other buttons of the VSX-859 would operate in conjunction with the stadily pressed STANDBY button.
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We are searching for the internal info from Pioneer service
I cannot and will not believe (or "accept"), that the Pioneer technical experts worldwide did not have a solution, to reset a faulty mainbord or a faulty memory configuration. It was 2000 to 2001 and the VSX-859 mainboard must have been loaded - within the receiver or within a laboratory service environment - with the last edition of the VSX-859 microcontroller firmware.
But the old Pioneer company is gone and all service workshops have been closed. There must be some documentation left in one of the former service locations. For example, we did pickup all Panasonic consumer videorecorder manuals from all years of sales within 2 pickup cars - from a closed service location near Frankfurt, well accepting, that 98% of the manuals would never be opened again - forever.
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Checking the frontpanel buttons of a VSX 859
Firstly we must learn, that the entire frontpanel ist activ in standby-mode.The chip, decoding the single buttons is working, but not the display-chip.
Reading many posts regarding factory reset of the main cpu, we did veryfy, that almost all "RESET procedures" do start with pushing a combination of a dedicated button and the "power on" button.
So we did check all buttons on the VSX 859 frontpanel one after the other - constantly pushing - and with a short delay - simultaneous pushing the power-on button.
Result : Only 2 buttons allow this procedure.
