Why configuration prints are blank in xerox 7500?

This printer is not capable of printing full bleed. You will have to print on oversized paper and trim it to get dull bleed.

Have you tried cleaning the sensors???

First download and install printer's driver ..click here Select your operating system and language. Next try to print the configuration page ..--> Press the [Up] or [Down] arrow button on the Control Panelto select [Printer Setup] on the Display Screen, and then press the [OK]button. Press the [Up] or [Down] arrow button to select[Configuration Page], and then press the [OK] button to print. Press the [Up] or [Down] arrow button to select [Exit], andthen press the [OK] button to return to the Main Menu.

To print a configuration page from a Xerox Phaser 3500:

- Press the Menu button
- Information will be displayed on the screen -- press OK
- Go to Info Pages, and press OK
- Go to Config Page, and press OK

To get configuration page instructions for other copiers, printers, or fax machines, go to How to Print Configuration Pages.

1. On the control panel, press the Menu button, then press the OK button to select

Information.

2. Select Info Pages, then press the OK button.

3. Select the appropriate information page, then press the OK button to print.

Note
Print the "Menu Map" to see other information pages available for printing.

Hope this helps

Kevin

If you put Tray 2 in Tray 1's spot with the heavy stock in Tray 1 (now in tray 2's spot) and print from it, does the problem persist?

This may help...
http://www.support.xerox.com/support/phaser-7500/support/enus.html?objGUID=4538

That is normally caused by a bad developer housing.

That really sounds like the imaging unit cleaner has an issue.
If you have one try the imaging unit, I really suspect that is your problem.
Black is Faded or Missing Step 1 Clean the Laser Windows and Remove Excess Toner From the Imaging Unit Step 2 Check or Replace the Imaging Unit Gear Retaining Pin Step 3 Replace the Imaging Unit (installation instructions)
See if this link works. Xerox is infameous for these not working.
http://office.support.xerox.com/SRVS/CGI-BIN/WEBCGI.cgi/,/?St=842,E=0000000000019251353,K=6024,Sxi=13,Case=obj(19377)