MX-M450N Background in duplex copy cis side

[fortwokaone]

Hi every body,

Need your help.
I am getting background on MX-M450N when copying in duplex mode on cis side. I tried doing adjustment 46/63 mode. Also tried replacing the CIS unit all circuit boards checked all the ok. Replace whole scanner unit machine works fine. What can go wrong in scanner unit so that it gives background only on cis side.

Thanks

[MHeon71]

Could it possibly be picking up outside light, as if the DF is not laying flat on glass. I have seen happen with the lamps and mirrors, not sure if it could happen with the CIS.

[OMD-227]

During production, the shading correction data for the CIS unit is stored within the EEPROM of the scanner control PWB. Since each CIS element has individual differences, the shading correction data is unique to the CIS unit installed, therefore, if the CIS unit or PWB is replaced, shading correction must be performed.

Unlike the CCD unit, the operation for shading correction with the CIS unit is only performed by using Simulation 63-02. After that, correction for each individual CIS element is not performed, but an operation to correct the entire output level is adjusted according to the degree of contamination.

With the CCD unit, the operation for shading correction is performed automatically
when the machine is powered on or every time it comes to the specified conditions.

Shading correction for the CIS unit must be performed by using Sim 63-02 (DSPF SHADING).

Procedure:
1. Clean the CIS & filter.
2. Clean the glass.
3. Close ADF
4. Enter Sim 63-02 and select DSPF SHADING mode.
5. Press the Start key.

The operation for shading correction is performed. When the operation has

[spotlifter]

You might wanna check the hinge behind. There's a black screw kinda type 'allen'. Also you can try shading(sim63). Good luck.

[Toner Boy]

Just a couple thoughts. We have noticed that the more a page is run through these machines (recycling paper) the more background you will get (especially if your developer is old or the mag roller has toner buildup on it). Also if the paper is moist/cold like warehouse location etc., duplexing paper is more likely to background as well. This will only cause light backgrounding and may not apply if you are experiencing something more significant.

[glewisme]

I agree with WAZZA, ran into this a ton of times and performing the shading 63-02 worked on them all.

[blackcat4866]

Here's my 0.02:

At one point we had a tech that tried to adjust SPF skew by shifting the SPF squareness. That worked fine in the 80's on the analog machines, but in this case it creates other problems.

If the white plate does not line up with the CIS you can get anything from background to black copies. The simple solution is get out your millimeter scale. Lower the SPF as far as you can (and still measure). Measure the distance between the right edge of the slit glass and the left edge of the black SPF mylar. Check this measurement back at the hinge, and all the way to the front. Adjust the right SPF hinge until that dimension is the same. Then run sim 63-02 like wazza says. =^..^=

[bilyahn]

I have also found it to help by placing 3 sheets of paper between the DSPF when you do the white reference. It cuts down on reflections and gives you a nicer image.

Good luck.

Bil