Canon -Load Paper Error

[Trigger 37]

Hope someone has seen this an knows what the problem is. I'm working on a MP730 printer that had the famous "Double Feed" problem where the paper feed mechanism gears got out of sync. I've fixed this problem on other printers before using the Product Service Bulliten from Canon. I'm sure I reset the gears to the correct position. The problem with working on MP730 or any all in One printer is that once you think you have fixed the problem, you don't really know until you re-assembly the entire printer. That is the only way to test it. This takes re-assembly of about 15 different parts, 19 cables, 24 screws, and a lot of patients.

However, with this printer as soon as I got it back together, the power on sequence was great and it came ready with a good green light, but as soon as I try and print anything, it produces an error, "Load Paper". It really never even tired to feed paper even though the internal mechanism did some cycling. My question is,.."Is there a separate Paper Sensor that could be broken, as this printer things there is really no paper in the document feeder, and clearly there is. Whatever original failure or jam that caused the gears to get out of whack could have also messed up the paper position detector. I see on the wiring diagram that there is a paper sensor, but I have never found it.

Any suggestions would be greatly appreciated. If we can get an answer to this, it should help many other people that ever get this kind of error. I say this because the complete carriage asm for the MP730 is identical to the i550, i560, series. The MP730 even uses the printhead from the i560. The paper feed mechanism is identical. My real problem is taking one of these guys apart takes a lot of time and I want to know what to look for as I remove piece by piece. I searched the Canon FAQ for this problem and the answer I got was,..."Add some paper".

 

[Bithead]

You know Trigger, you got some big nuts. Here your are asking for help/information about a problem you are having and you want someone to give you the answer for free so you could resolve your issue and probably include it in one of your 'manuals' but you wrote in some other post:

"Please don't waste time asking for any of these for free,.. but we can make a trade. Let me know what you have and, "Let's make a deal""

If I knew the answer I would not give it to you.

 

[Trigger 37]

Bithead,... Yes I guess I do after all. On the other hand if you go back and look at many of the posts that I have made, I have provided helpful information to lots of people in any way I can. I have also put a lot of time and effort into the Repair manuals I sell. The Service Manuals I have I had to pay for and they are original Canon Manuals. If I was to give them away I would have 1000 requests in one day. I don't have that much time as I do have another life. I am missing several HP manuals and a couple of Epson manuals and if anyone needs one of the manuals I have, hopefully we can make an exchange. I will continue to help people as I can but there is a limit to my time.

Some of the things that go wrong with printers require someone to take the printer totally apart. The Repair Manuals that I offer go into complete detail on how to do this and include high resolution photos that show them what and how to remove and repair items. The advantage of the PDF files I offer is that the photos can be zoomed up to 300-500% such that even small details are visible. The manuals contain 9 chapters that cover everything from Diagnostics, printhead cleaning, disassembly, to Preventive Maintenance. The typical PDF is 15 MBs long and is 100's of pages. When someone needs some of this information, there is no way I could post it on this forum,.. it would overload. If anyone went on eBay just to buy the standard Canon Service Manual for their printer they would pay anywhere from $5.00 to $10, and this would not include the Parts Catalog. I provide both of these and my Repair Manual for each printer, along with every other document and software that Canon provides for each printer. Last but not least, I provide continued updates to these Manuals as I create them. For each printer I repair, I learn something new and when I do I add the information to the manuals.

I am currently in the process of adding more printers to the list I support. I have about 45 printers to work on at this moment. I learn something from each printer. Why do I do this,...because I am retired, I have some time, and I believe it will help many people fix there printers and stop them from dumping them in the trash. It also provides me a VERY FEW dollars to help with my retirement.

Getting back to my nuts,...Even when I post a problem that I'm having with one of these printers, I am very honest about it. I don't try to hide anything. I believe that others LEARN something from just reading my posts because I provide as much information as I can. Others complain that I provide too much information. I guess you can please some of the people most of the time, but never try and please all of the people all of the time.

 

[Trigger 37]

Well after "Bithead", made his comments about my "Big nuts", no one has added any information to this post. The good news for those of you that have a Canon MP730 is that I found the problem and fixed the printer. It was not a nice fix but a necessary one.

The problem started out with the customer saying that the printer would double feed paper which is a classic MP730 printer problem. I took the printer apart and reset the ADF gears to the correct index mark and put it back together. That short sentance is about 2-3 hours of work. As my post above indicates the printer then got nothing but "Paper Feed error" or "Load Paper". So since I got no help from anyone else I took it apart again and got into close examination. It turns out that one of the plasitc shafts that controls one of the gears was broken and the gear was not actually meshing with the other gears to feed any paper. The action which causes this problem to start with is some kind of paper jam or a power failure while the printer is actually printing something. People tenk to panic when a paper jam occurs and try to yank the paper out of the printer while it is still attempting to feed. This really causes a problem as now there is strain on the gears in two direcrections. This not only pulls the gears out of sync but in this case broke one of the tiny plastic axles or shafts that the gear rides on. This shaft is only 1/2" long and not quite 3/16" in diameter. It is more like a plastic molded tit off of the ADF plastic housing. It is all one molded part. So when you add a lot of stress to the gear, something has to give.

So the fix was nothing short of buy a new ADF unit for the MP730. I must say that this part from Canon was very reasonable and the Customer was very happy that when I installed the new ADF the printer is now as good as new, at a very reasonable price. Plus he is going to get my MP730 Repair Manual as part of any printer I refurbish. I now can add another symptom & probable cause to my MP730 diagnostic list. Just a little warning to others. This has got to be the most complex printer to take apart and repair that I have ever worked on. It is just as hard to put back together. If you get one thing wrong, or leave out one screw or forget one wire, then you are about to take it all apart again.

So this should end this thread with another success story,... unless someone has another question about MP730 printers.