Toshiba e-STUDIO500P manual Print quality-banding

	FRU	Action
4	System board HVPS	Check the following voltages at J15 on the system board. Measure
	connector	the voltages from J15 to printer ground.
			Pin J15		Voltage (approximate)
			Printer idle
			J15-1	0	V dc
			J15-2	+4 V dc
			J15-4	0	V dc
			Printer printing
			J15-1	0	V dc to +5 V dc
			J15-2	0	V dc to +4 V dc
			J15-4	0	V dc to +1.9 V dc
		If J15-1 voltage is incorrect, check the continuity of the front harness
		cable (J15-1 line). If there is no continuity, replace the harness cable.
		If there is continuity, replace the HVPS. If this does not correct the
		problem, replace the system board.
		If J15-2 voltage is incorrect or if the voltage remains at 0 V dc, check
		the continuity of the front harness cable (J15-2 line). If there is no
		continuity, replace the harness cable. If there is continuity, replace the
		HVPS. If this does not correct the problem, replace the system board.
		If J15-4 voltage is incorrect, check the front harness cable (J15-3
		line). If there is not continuity, replace the harness cable. If correct,
		replace the system board. If this does not correct the problem,
		replace the HVPS.

Print quality—banding

Service tip: Banding is difficult to detect, except on a page with a uniform gray or a large amount of graphics printed on the page. Banding is primarily due to a variation in the speed of the paper as it feeds through the printer, especially in the development and transfer process. Inspect the alignment assembly, main drive assembly, and all other paper feed components for signs of wear, dirt, binds, or damage, especially the drive gears. Banding appears as light or dark horizontal lines on a uniformly gray page.

Banding can also be caused by a defective charge roll brush contact or HVPS. Check the charge roll contact for damage and for proper connection to the HVPS and print cartridge.

Diagnostic information 2-119