Apple Color LaserWriter 12/600 PS General Maintenance

Levelling the printer with the spirit level on top of the fuser (Apple Service Source drawing)

Routine care for the Apple Color LaserWriter 12/600 PS and the Apple Color LaserWriter 12/660 PS, whose engine, plastics and service parts are identical. It is taken from Apple's Service Source for both printers and the 1995 Service Guide. Apple's procedures are for replacing consumables at the points the printer reports, cleaning, levelling and handling the fuser oil. The Service Source has no lubrication procedure.

Safety

• High voltage: switch the printer off and unplug the power cord before servicing. Do not be grounded when working on plugged-in equipment or making live adjustments.
• Laser: the beam inside the laser/scanner assembly is invisible (780 nm) and can harm the eyes. Never take the laser/scanner apart; Apple does not supply its parts and it cannot be adjusted in the field.
• Fuser: it becomes very hot. Switch off for at least five minutes before servicing the fuser assembly. Its heaters are 485 W (100-120 V) or 430 W (220-240 V); the safety circuit cuts them at a thermistor reading of 217 °C and the thermoswitches at about 230 °C.
• Weight: about 50 kg for the printer body alone. Lift with care.
• Static: the I/O controller's CMOS parts, ROMs and SIMMs are very sensitive to static and skin acid; handle them by the edges.
• Toner: remove it from skin or clothes with a dry tissue, then wash in cold water. Keep it away from vinyl.
• Ozone: the charging roller and separation discharge assembly produce small amounts of ozone in operation.
• Fuser oil: it is very slippery on hard floors; wipe up spills at once.

Consumables and when to replace them

The status panel lights tell the user when to order each consumable.

Consumables (Service Source; Service Guide Vol. IV)

Item	Apple's figure or trigger
Toner cartridges (C, M, Y, K)	About 4,000 pages per colour at 5 % coverage
Photoconductor cartridge	40,000 black-and-white or 10,000 colour pages in continuous printing; supplied only in the Photoconductor Replacement Kit (M3761G/A)
Toner disposal box (922-1546)	Alert light flashes and the disposal box light comes on when full
Fuser assembly	Recommended maintenance interval 60,000 pages. When the cleaning belt sensor trips, the fuser light comes on and the printer allows 500 more prints before stopping
Fuser oil bottle (M3755G/A)	When the oil-low sensor trips, the oil light comes on and the printer allows 50 more prints before stopping
Transfer drum cleaning unit; air and ozone filters	Supplied in the Fuser Replacement Kit; replace with the fuser

Photoconductor cartridge

Use the orange photoconductor tray whenever the cartridge is out: the drum is light-sensitive. A new photoconductor zeroes the life counter on the DC controller, so taking a new cartridge out and refitting an old one makes the old one count as new. Before swapping photoconductors to isolate a fault, save the controller board parameters with the Color LaserWriter Service Utility.

Fuser and oil bottle

Open the fuser access door and paper pickup door, lower the clamp over the oil compartment and lift the bottle out, keeping it upright on a paper towel: a valve in the lid stops the flow but some oil may drip. The fuser is held by two captive locking screws. A replacement fuser must match the mains voltage, and its two captive screws must be fully tightened.

Fuser oil extraction

A fuser going back to Apple must be emptied. One syringe and a sealing block come with the replacement fuser (syringe also 922-1549).

1. Pump the green jam release lever 50 times to return oil in the system to the reservoir.
2. Draw the oil from the bottom of the reservoir with the syringe and inject it into the replacement fuser's reservoir; repeat until none is left. Seal the old reservoir with the sealing block.
3. If the printer reported an oil pump (overflow) error, also raise the gear end of the fuser, remove the well cover and cap on the delivery side, and draw the oil out of the overflow well.

Separation discharge assembly

Open the front door and the top cover, release the tab, press the assembly slightly to the right and lift it out; slide the new one left to lock it.

Levelling

Apple stresses that the printer must stand on a perfectly level surface: out-of-level surfaces cause oil overflow errors. The 12/660 PS came with a spirit level and rubber shims (also sold for the 12/600 PS as kit 076-0622); place the level on top of the fuser, front to back and then side to side, and shim the feet. Apple's 1996 bulletin allows any flat, incompressible shim (it suggests sticky notes, card or magazines) under the plastic feet, and shows a tolerance of 0-15 mm, 0° to +2°, front to rear. A 12/660 PS also has two orange spacers and oil absorption sheets in and around the fuser for shipping, which must be removed after levelling.

Cleaning

• Clean the density sensor and the separation discharge wire with the brush supplied, and the paper pickup area, as the user guide describes; then print ten blank pages to clean toner off the rollers. Apple gives this as the cure for small amounts of toner on printed pages.
• Use cotton gloves when handling the transfer drum, and a vacuum designed for xerographic copiers.
• Marks that repeat down the page come from a dirty or damaged roller. Apple's table gives the repeat interval for each roller (134 mm for the fuser rollers, 129 mm for the photosensitive drum); the full table is in the troubleshooting guide.

Moving the printer

Before moving the printer a long distance, remove the toner disposal box and the photoconductor cartridge. Extract the oil from the fuser before moving it: if the printer is tilted with oil present, oil can contaminate the overflow sensor and cause an oil pump error that needs service.

Related pages

• Apple Color LaserWriter 12/600 PS and Apple Color LaserWriter 12/660 PS
• Apple Color LaserWriter 12/600 PS Troubleshooting Guide
• Color LaserWriter 12/600 PS and 12/660 PS Service Source