Apple eMac

Apple eMac

Apple eMac (model A1002)
Specifications
Manufacturer	Apple Computer, Inc.
Type	All-in-one personal computer
Released	29 April 2002 (education); 4 June 2002 (retail)
Discontinued	July 2006
Intro price	US$999 and US$1,199 (education, 2002); US$1,099 (retail, 2002)
CPU	PowerPC G4 at 700 MHz (2002); later 800 MHz, 1 GHz, 1.25 GHz and 1.42 GHz
Memory	128 MB PC-100 SDRAM (2002 models); two DIMM slots
Storage	40 GB ATA hard disk (2002); up to 160 GB on the 2005 models
Display	Built-in 17-inch flat CRT (16-inch viewable), up to 1280 × 960
Sound	—
Graphics	NVIDIA GeForce2 MX (2002); later ATI Radeon 7500, 9200 and 9600
Media	CD-ROM, CD-RW or DVD-ROM/CD-RW combo drive (2002); later SuperDrive options
Ports / interface	3 × USB, 2 × FireWire 400, mini-VGA, 10/100BASE-T Ethernet, 56K modem (some models), headphone and audio in
OS / Firmware	Mac OS X 10.1.4 and Mac OS 9.2.2 (2002)
Model no.	A1002

The Apple eMac is an all-in-one Macintosh with a built-in 17-inch flat CRT and a PowerPC G4 processor. Apple announced it on 29 April 2002 as a desktop designed for education customers, at US$999 with a CD-ROM drive or US$1,199 with a DVD-ROM/CD-RW combo drive and modem. On 4 June 2002 Apple began selling it to the general public in a CD-RW and modem configuration at US$1,099.

Apple revised the eMac several times up to a 1.42 GHz model in May 2005. In October 2005 it was again limited to education buyers, and on 5 July 2006 Apple announced that a US$899 education configuration of the 17-inch Intel iMac would replace it. Apple's announcement described the eMac as "Apple's last CRT based computer".

Apple's eMac Service Source, updated 15 January 2004, covers the 700 MHz machine. Later eMacs differ in detail, so check the model before relying on a part number.

Specifications

eMac (2002) specifications

Item	Specification
Processor	700 MHz PowerPC G4 with 256K on-chip level 2 cache; 100 MHz system bus
Memory	128 MB SDRAM fitted; two 168-pin DIMM slots, up to 1 GB using 128, 256 or 512 MB PC-100 modules
Optical drive	Tray-loading CD-ROM or DVD-ROM/CD-RW combo drive (education models); CD-RW (retail model)
Hard disk	40 GB ATA
Display	17-inch flat CRT, 16-inch viewable, 0.25 mm dot pitch; 640 × 480 at 138 Hz up to 1280 × 960 at 72 Hz
Graphics	NVIDIA GeForce2 MX, AGP 2X, 32 MB DDR SDRAM
Modem	56K V.90; on the education models, fitted only to the combo-drive model
Power	100 V AC or 220 V AC depending on country; 47-63 Hz; 170 W maximum continuous
Size and weight	40.6 × 40.6 × 43.3 cm (15.8 × 15.8 × 17.1 in); 22.7 kg (50 lb)

The eMac uses a different mains cord from older iMacs, and an iMac cord may not fit its socket.

Later models

eMac revisions

Processor	Introduced	Graphics	Hard disk
700 MHz G4	April 2002	NVIDIA GeForce2 MX	40 GB
800 MHz G4	August 2002	NVIDIA GeForce2 MX	60 GB
800 MHz and 1 GHz G4	May 2003	ATI Radeon 7500	40, 60 or 80 GB
1.25 GHz G4	April 2004	ATI Radeon 9200	40 or 80 GB
1.42 GHz G4	May 2005	ATI Radeon 9600	80 or 160 GB

The 2003 ATI models kept three USB 1.1 ports; USB 2.0 arrived with the 1.25 GHz model, which also moved to 184-pin DDR memory.

Ports and accessories

The launch eMac has three USB 1.1 ports on the computer and two on the keyboard, two FireWire 400 ports, 10/100BASE-T Ethernet, a 56K modem on the models that have one, a headphone jack, an analogue audio input and a mini-VGA output that mirrors the internal display (a VGA adapter is needed). It has a 16-watt amplifier, stereo speakers, a built-in microphone and a slot and antennas for an AirPort card.

It shipped with the Apple Pro Keyboard and Apple Pro Mouse. Apple sold the eMac Tilt and Swivel Stand (M8784G/A) separately; the Service Source gives its fitting procedure, which uses a 4 mm hex wrench.

Apple eMac with the tilt and swivel stand, Apple Pro Keyboard and Apple Pro Mouse

Servicing

Apple's take-apart tools are a 2.5 mm hex key for the rear housing, a No. 2 Phillips screwdriver, jeweller's screwdrivers, needle-nose pliers, an ESD wrist strap and mat, and a CRT discharge tool. Apple says not to use a power driver on the rear housing screws.

The display/analogue assembly needs no voltage calibration or geometry adjustment. If focus, colour or brightness look wrong, use the Displays preference pane (Mac OS X) or the Monitors control panel (Mac OS 9); if that does not correct it, Apple's cure is to replace the assembly.

Reset the PMU

The Power Management Unit (PMU) is a microcontroller that turns the computer on and off, handles sleep and system resets, and maintains parameter RAM and the real-time clock. Apple warns that touching the logic board circuitry can crash it, and that a crashed PMU cuts battery life from about five years to about two days. Apple's instruction for a unit that fails to power up is to reset the PMU before replacing any module:

1. Shut the computer down and remove the user access door.
2. Unplug every cable except the power cord.
3. Touch a metal surface inside the computer, then unplug the power cord.
4. Press the PMU reset button once. A second press can crash the PMU.
5. Wait ten seconds before reconnecting the power cord and switching on.

The reset also clears PRAM, so the date, time and other settings must be set again.

Logic board battery

The battery keeps the system settings and powers the PMU clock while the computer is unplugged. Apple recommends removing it whenever the logic board is handled. Test it in its holder (under load) across the positive and ground terminals. If it does not read at least +3.5 V, replace it and reset the PMU. A drained battery may indicate a crashed PMU. The service part is 922-4028.

Power-on self-test beeps

The eMac runs a self-test from ROM after a full shutdown (not on a restart). A fault replaces the startup chime with beeps:

eMac error beeps

Beeps	Meaning
One	No RAM installed or detected
Two	Incompatible memory (the slots take standard PC-100 or PC-133 168-pin DIMMs)
Three	No RAM bank passed memory testing
Four or five	Bad checksum for the remainder of the boot ROM; the ROM is bad

Mains voltage jumper

The display/analogue assembly contains a non-switching power supply preset for 220 V. It does not sense the mains voltage: a voltage jumper on the assembly must be fitted for 110 V operation. A second jumper serves the LHR line-conditioning module fitted in some countries.

Apple's jumper settings

Supply	Voltage jumper	LHR jumper
110 V	On	On
220 V, no LHR module	Off	On
220 V, with LHR module	Off	Off

A replacement assembly arrives set for 220 V. Wrong jumper settings are the first item in Apple's Random Shut Down chart. Apple lists the assembly under two part numbers, 661-2634 (Northern Hemisphere) and 661-2635 (Southern Hemisphere).

No power

Apple's No Power chart works outwards from the mains. Its measurable steps are:

1. Check the outlet, the power cord and both ends of its connection; remove the keyboard, mouse and other peripherals.
2. Rest the computer on its CRT face, remove the user access door, touch a metal surface inside, then unplug it.
3. Check the battery reads at least +3.5 V; if not, replace it and reset the PMU. Then reset the PMU.
4. Remove the rear housing and discharge the CRT.
5. Try a known-good power button.
6. Make sure the ground screw is attached to the frame before testing power, and check the AC connector is connected.
7. With the computer unplugged, check fuse F901 for continuity. A reading of 0 Ω means the fuse is good; an infinite reading means the display/analogue assembly should be replaced.
8. Plug in and check for line voltage (120 V in Apple's text) at the AC connector. None means the display/analogue assembly.
9. Check for 5 V trickle on capacitor C3202, near the modem board on the logic board. No 5 V means the display/analogue assembly.
10. Check the down-converter connector is seated. With the unit plugged in but not switched on, measure pin 1 of P801 on the down converter against the frame. A reading of 10.5 V to 17.5 V means the display/analogue assembly is at fault; outside that range, the logic board.

No video

For no picture on the internal display with the fan running and drive activity, Apple's order is: reset PRAM (Command-Option-P-R at startup); start up from the system CD; reset the PMU; then connect an external monitor to the video-out port. If external video works, replace the display/analogue assembly; if not, replace the logic board.

Vertical raster shift

If the raster moves up until the menu bar is hidden, Apple's cure is to replace the IVAD cable (922-5806). Both ends are glued into their connectors. Remove the glue with a nylon probe tool (922-5065) or needle-nose pliers, softening it with a heat gun if necessary, and re-glue the new cable with hot-melt glue.

Thermal paste

The G4 is cooled by a heatsink and heat pipe. Whenever the heatsink is removed, clean both mating surfaces and apply fresh thermal paste, or the processor may overheat and be damaged. Apple specifies a plastic stylus or nylon probe tool (922-5065) for cleaning and thermal paste 922-4757; each tube holds four or five applications.

The hard drive may carry up to three thermal pads. The two on top may be discarded when the drive is replaced; replace the side pad if it is damaged.

Service parts

Part numbers from the exploded views of the 700 MHz Service Source:

eMac (700 MHz) service parts

Part	Apple part number
Display/analogue assembly	661-2634 (Northern Hemisphere), 661-2635 (Southern Hemisphere)
Down converter	922-5067
Hard drive, 40 GB	661-2633
Optical drive	661-2639 (CD-ROM), 661-2640 (CD-RW), 661-2646 (CD-RW/DVD-ROM)
Modem, without RJ-11 cable	661-2632
DIMM, SDRAM	661-2398 (128 MB), 661-2399 (256 MB)
Battery	922-4028
Fan assembly	922-5083
LHR, CRT	922-5191
Speaker assembly	922-5081
Power button with cable	922-5075
User access door	922-5076 (110 V, USA), 922-5222 (220 V)

Known faults

In June 2006 Apple announced a repair extension programme for eMacs built between April 2004 and June 2005 that showed scrambled or distorted video, no video or no power "as the result of a specific component failure". It covered repairs for up to three years from the date of purchase. Apple did not name the component.

Apple's Service Source is module-level. The display/analogue assembly and the logic board are replaced, not repaired, and the only individual components it names are fuse F901, capacitor C3202 (as a 5 V test point) and connector P801. It gives no capacitor values; read them from the board itself. See Capacitor Failure Symptoms for what failed electrolytics look like.

Documentation

• eMac Service Source (Apple, updated 15 January 2004): take-apart, troubleshooting, symptom charts, upgrades and exploded views for the 700 MHz model.

Related pages

• CRT Discharge Procedure
• Capacitor Failure Symptoms
• Macintosh Repair Resources