On a recent service call, my customer complained to me that their HP LaserJet P4014 was having some print quality issues. When I printed a test page I noticed that there were several areas down the left side of the page that had light print. My first thought was to replace the toner cartridge but the customer informed me that they had already done so but the problem had been on-going.
Since the light print was not consistent down the page, but happened at intervals, I knew right away I could rule out the laser scanner assembly as the problem. After running a half test and confirming that the defect was on the page before the image was fused, I knew it was either the transfer roller or toner cartridge. Continue reading