[Error Code] C-6753 error on 754e

[nullskull]

I was taking apart the DF-704 in order to replace the rollers and such. Of course the spring underneath the bottom feeding roller housing popped out into the area where the CIS module is. I tried using a magnet to fish it out but didn't work. Eventually i just opened it up and pulled the spring out from under the CIS board. I then put everything back together and now the machine is giving me a C-6753 code. I've looked at all the connections for the CIS and even reseated them. But the code continues. On startup the first two times the machine tried clearing the codes. But now it goes straight to the error. I've noticed the the motors never spin up before the code appears except for the one powering the roller underneath the CIS Module. My question is should I check anything else? The magnet I used is small but not weak. Could that have damaged the CIS by having it pass over/around? Or could it be something to do with the belt in the back of the unit?

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[Woxner]

I am going to assume you did a trouble reset or system clear for the code. If you did and still have the code you probably need to replace cis and or pwb

[nullskull]

I am going to assume you did a trouble reset or system clear for the code. If you did and still have the code you probably need to replace cis and or pwb

Hello Yes I tried trouble reset twice and no change. I'm just so confused cause it seems like i didn't do anything to cause a board to fail.

[nullskull]

Are these the timing belts that usually get messed up? The part circled on the left is the wheel with a sensor around it.
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[femaster]

Was the machine powered on when this happened? Is it possible the spring shorted something out? Check ICP1 on the CIS power supply board...


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[nullskull]

Was the machine powered on when this happened? Is it possible the spring shorted something out? Check ICP1 on the CIS power supply board...


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Hello, yes I forgot to mention that. Either the spring or the magnet I used to try fish it out could have done that. The ICP1 is a LED I'm guessing?

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I don't see any lights on the CIS (right picture)

[nullskull]

If the CIS is the issue then I have a spare in a different machine i could swap and see if that solves it?

[femaster]

Hello, yes I forgot to mention that. Either the spring or the magnet I used to try fish it out could have done that. The ICP1 is a LED I'm guessing?

The ICP is a fuse, not an LED. The power supply board for the CIS is what would have the blown fuse (ICP1). It is a very small circuit board located just to the left of the CIS assembly if looking from the front of the machine. Check the fuse (ICP1) on the board for continuity. If there is none, then you know the fuse blown. This is where the board is located:

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If the CIS is the issue then I have a spare in a different machine i could swap and see if that solves it?

You could swap out the CIS, but you can also try the power supply board from that parts machine. Test the original power supply for the blown fuse first before swapping anything. You might save yourself a lot of time if that is all that is wrong.

[nullskull]

Ok, I found it. The board looks good.
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That's the fuse just above the plug on the right hand side.
My next thought would be to replace the main black cable on the CIS board.

[nullskull]

There is a bulletin saying to check voltages.

1. Voltage
Please confirm the voltage of No.1 ˜ No.3. (No.2 and No.3 are same connector.) If the voltage is not output, cable (a) Main cable (p/n A3CE PP4Q 01) or (b) CIS cable (p/n A3CE N117 00) is suspect and may need to be replaced.

Which connectors should I check? Are the connectors I should measure on the power board as pictured above? Or on the CIS board?