Print-Image Quality Specifications - Xerox 3400N - Phaser B/W Laser Printer Service Manual

Use A4- or letter-size paper when troubleshooting an image-quality problem. Verify the
Remote Control Panel settings to determine whether an image-quality problem is being
caused by the printer or by the PC. If the configuration page prints normally, but in the
online mode the prints have an image-quality problem, the problem may be in the System
Controller Board, Interface Cable, or with the Host computer.
24 Xerox Phaser 3400 Printer Service Guide