Repairing the HP P4014 and M601 Series .

Most Repairs Don't Need Dismantling

Many faults with these printers will be cured by changing the cartridge, so unless you are certain the fault is somewhere else do that first.   Opening a new cartridge should not be "wasting it" (as might happen with an inkjet) since these laser printers are almost invariably repairable.   Keep any part-used cartridges in the bag, sealed with sticky-tape in the box and in a cool dark space. Cartridge drums are light sensitive and their properties decline if left exposed for as little as an hour.

Paper Jams and paper feed faults are most likely to be the soft rollers. These can be replaced at low cost with a feed repair kit. Rollers just slide onto their shafts, see here

Blotches on the page that are not explained by the cartridge are most likely to be the fuser. These printers are a little unusual because the fuser is easily removed (see below).   The printer will prompt for a "maintenance kit", which includes a fuser, a little beyond 200,000 pages.

Before setting out on any repair its a good idea to check the printer's own error log which is visible through its internal Web Server at the printer IP address. See the summary here

To remove the fuser push up on the blue latches whilst withdrawing the fuser from the rear of the printer. A bit of gentle wriggling may be needed to get it free of the connector socket on it's inner face.

The fuser exit assembly can be opened to look for damage to the sleeve. Turn the sleeve using the big brown cog as though it was feeding paper - it is stiff - there is a very substantial load from the pressure roller.

The formatter cover sides off to the rear.

The formatter is held by two thumbscrews and slides out to the rear. The formatter is a scattering of memory, Ethernet and USB support chips around one large PMC-Sierra chip. The formatter itself does not seem to be a significant source of problems. The printer should report error "79.xx" if the formatter fails. Firmware is a known source of problems but that is changed by uploading another ".RFU" file ( ie an updated firmware).   Only HP can supply firmware - don't download it elsewhere.

The option cover at the top rear of the printer just unclips upwards.

This is the point in disassembly where ordinary users stop. Further work means wielding a screwdriver.

Removing the Covers

There is nothing obtuse about working on the P4014 or M601 series printers so workplace based and field service technicians will have no difficulty. Users venturing into the field need to be aware that printers are not like PCs - high voltages are present if the device is plugged in, the laser is a possible hazard and the motors could be. You are at risk from the circuits. The circuitry is at risk from your handling it. Manufacturers often put "no user serviceable parts inside" stickers on equipment. Actually there are parts in this printer that a knowledgeable user with a tech-support background can change.

Tools recommended are
● #2 Phillips screwdriver with a magnetic tip and a 152-mm (6-inch) shaft length
● a small flatblade screwdriver, sometimes called a terminal screwdriver.
● Needle-nose pliers
● An anti-static strap

The screws are mostly M3 and M4 sizes in silvered and Japan lacquered types.

To remove the covers, first disconnect the cartridge door link arm. The service manual says to use needle nose pliers but practice shows it can be done with finger-nails.

The paper cassette tray probably needs to be removed since it is likely to be in the way later.

The top cover is held in place by four screws, two at the rear under the output accessory cover and two visible with the cartridge door lifted.   With the screws out the top cover lifts away.

The right cover is held by one clip in the top middle and another at the rear juncture with the right-rear cover. With these released the cover folds down away from the metalwork on hinge points along the bottom. A little effort is needed to overcome the tabs at the front.

The significant release tab for the left cover is inset a bit and engages a slot in the metalwork. Push it down. The side folds down but needs a bit of wiggling to clear the curved MP tray front cover.

The right rear cover just unclips from the metalwork.

The right front cover is more trouble. First remove the envelope feeder cover marked with a number "1" as it is over one of the screws. There are three screws and a clip holding the cover in place.

Dismantling the covers more or less has to follow the sequence: accessories out, top off, right side off, right-cover off, and then front cover. Each interlocks with it's predecessor. There is no particular point in taking the left cover off unless you want to get at the fans and thermistor but it isn't difficult.

Next Section - removing the innards here.