HP Laserjet 4500N Print Fades

[Bryan]

We have a 4500 that prints the first few pages fine, but about page 3 on, the print fades out to near nothing. As if it's running out of toner as it goes. This seems to be black only. We've changed the black toner and cleaned the transfer belt. Any ideas? Thanks

[MichaelTech]

What are all the consumable levels?
This could be a developer PCB, or a carousel going bad.
Is the Drum new? ITB new? HP or 3rd party products?
Clean the transfer "roller" {not the ITB}

[Bryan]

Changed the drum kit, toners and all else says it's at 90% or more. Still fades as it prints. Just gonna call a tech out to take a look at it. Thanks for the help.

[redcow]

Just a thought....what's it plugged into, the wall outlet(dedicated circuit) or a power strip?