MP 830 won't power on

[jimbo123]

MP830s are getting up there in years, they came out in 2006, so they are 11 years old.

i have a few working 830s and a few i use for parts. once working they are quite reliable.

i have not had any success resolving the "no power" problem, have not spent much time on it though.

attached is a copy of the "MP830 service manual", might help you.

one issue i have seen is the scanner unit fails, i can now swap in a new one in under 10 min.

the no BLACK issue is most likely the print head. since there are no new print heads you'd need to find a working one or roll the dice on a refurbished one on ebay from overseas.

my current 830 is banding on all the colors, but BLACK text is fine. again most likely the print head, but since i only use the 830 for text printing i'm OK with it. i have a MP980 i use for color.

again watch out for the "new 830" print heads on ebay from overseas, they are all "NEWLY" refurbished..... many have had bad luck with them

keep us posted

J

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• Active Printers: MP830, MP980, PRO-100
• Stored Printers: MP830, IP4500, MX700, MX860, MX870
• Method: German Durchstich Method
• Ink: Hobbicolors and OCP
• Misc: Squeeze bottles - so much easier than syringes

 

[PeterBJ]

The most likely cause of the MP830 printers refusing to turn on is defective print heads. See this post. Sadly Canon print heads can fail for no apparent reason, especially if they are old.

A print head that has failed electronically might damage the logic board, and a logic board that has been damaged in this way can damage a new print head. So replacing a Canon print head is a gamble and I cannot tell the odds for success.

I have an MP800 using the same print head as the MP830. It was working OK one day, but the next day after turn on the print head had failed. Both light magenta and pigment black have failed. I have tweaked the scanner settings to make the light magenta defect more clear:

 

[Hennmann]

The sad part about these printers especially the one I purchased new is they have very little use making me wonder if most are expensive junk! I decided to spend a great deal on this lemon fooling myself into thinking you get what you pay for but this wasn't the case. Even though I don't print much, I wanted something fantastic for when I did, not to mention the other features this lemon has including speed and photo quality, and the first color fax I have ever seen, but in reality the only speed it has is in dying. As for the manual, I have that one but gives very little information in diagnostics which sucks due to the number of boards within and how miserable most components are to get to! As it is my first new purchase died a number of years ago after the warranty ran out and because I paid so much made me hang on to it after all it wasn't a $99.00 printer and my recent purchase died when I lifted the top to perform a scan. That one I only printed 2 pages when I tested it before the fool and his money were soon parted. Is it possible to test the logic board by leaving the print heads disconnected? Also if the print head fails does this prevent the printer from turning on even though the logic board might still be good? Back when I joined this forum I disconnected the print heads in an attempt to try and figure why it wouldn't power on. I gave up because of the lousy manual not knowing what to replace even though some sellers on ebay had parts for sale, some NOS, some used. If I can swap the logic board with my "new" first printer with the printer head disconnected, will it power up? Also how does one test printer heads? Other than the one that doesn't print black, the other two dead units look brand new and I still have the original box for it. The ironic part about the second dead is it was fully powered on, showing up on my computer etc. and only died when i lifted the top to place what I needed scanned in the scanner. It was like somebody pulled the plug and as a result I swapped the power supply but it is still dead. There is a relay board, the logic board, the control panel and who knows what else making me wonder if both have the same problem. Sorry for my rant today but three identical printers surrounding me has left a bitter taste, not to mention no Canon Service center nearby (nearest city 50 miles away with 275,000, and another 150 miles away with 256,000 and no repair centers??) indicating lousy customer support!!

 

[Hennmann]

PeterBJ Thanks for your reply to my post and all of the information you have provided!!
Here is a quote from a link from the link you were kind enough to provide.

Schematic diagrams and other electronics info are rare in Canon service manuals, but the service manual for Canon Pixma 4200 has some electronics info. The power supply for the iP4200 has 3 output voltages: 16, 24 and 32 VDC, The output connector has 7 pins, one of them is for a control input from the logic board, as stated by turbguy.

Here is a table showing the pin out for the power supply connector on the logic board. As this connector is placed on the logic board inputs connect to outputs on the power supply, and the control output connects to the power supply control input.

Here is a picture of the logic board from a Pixma 4200. Note the presence of ferrite core inductors and electrolytic capacitors indicating the presence of voltage regulators for at least 5 VDC for USB and 3.3 VCD for sensors and logic in the printer. The power supply needs to have a standby mode supplying at least some voltage to the logic board, else the logic board cannot generate a control signal to start the power supply in normal operating mode.

So testing the power supply outside the printer will only show the lower standby voltage(s). A wild guess is that applying +3.3 V to the control pin and -3.3 V to one of the ground pins (which one?, the grounds might not be common) will start the power supply in operating mode. But beware, some switching mode power supplies can refuse to start or might even be ruined without a proper load.

The logic board drives the print head, among other things. At power up I think some test of the print head using the reduced voltage is done. If this test is passed the logic board sends an OK signal to the power supply. This explains why a defective print head can prevent the printer from powering up, and why sometimes after removing the print head the printer will start. A defective print head can also ruin the logic board, and a ruined logic board will most likely send no OK signal to the power supply.

So thanks to @turbguy for the electroda link that made me study the iP4200 service manual and figure out the interaction between the power supply and the logic board.

According to the druckerchannel.de forum Canon power supplies fail very rarely, instead failure to power up is caused by a defective print head and/or a defective logic board. I think this is very plausible.

If you want to study the schematics and tables, you find the iP4200 service manual here, and the MP610 service manual here, the MP610 manual doesn't have the electronics info, but might be handy in case of other errors. Before downloading the manuals from electrotanya, read this instruction.



After reading
The logic board drives the print head, among other things. At power up I think some test of the print head using the reduced voltage is done. If this test is passed the logic board sends an OK signal to the power supply. This explains why a defective print head can prevent the printer from powering up, and why sometimes after removing the print head the printer will start. A defective print head can also ruin the logic board, and a ruined logic board will most likely send no OK signal to the power supply.

Is it safe to assume that if I disconnect the print heads, AND swap the logic board, to see if it is possibly the logic board, it should power up if indeed it is a logic board? The sad part about this is the logic board sends the signal to the power supply to make it go from stand by to power on and none of this is mentioned in the repair manual. Another thought is what else CAN power on if the power supply is not in stand by? By this I mean, you have the control panel on the front, you push the button, the scanner lights up, the control panel lights up, the ink cartridges will move to the center to allow access, does this logic board control everything?? What else can cause the power supply to not go to power on?

 

[PalaDolphin]

A print head that has failed electronically might damage the logic board, and a logic board that has been damaged in this way can damage a new print head.

There's a nightmare scenario.