Macintosh Performa 5400 General Maintenance

Proper maintenance is essential to extending the lifespan and ensuring reliable operation of your Macintosh Performa 5400 series computer. The following sections provide guidance on routine maintenance and common failure points.

Regular Cleaning

Internal Cleaning

• Power down and unplug the computer completely
• Remove the rear cover to access internal components
• Use compressed air to remove dust from the logic board, power supply, and CD-ROM drive
• Pay special attention to the CRT neck board and flyback area
• Clean the floppy drive heads with a cleaning disk or isopropyl alcohol. The drive is a 1.4 MB Apple SuperDrive, which is direct drive — there is no belt to check or replace

External and CRT Cleaning

• Clean the CRT screen with a damp, lint-free cloth or dedicated screen cleaner
• Avoid spraying liquids directly on the screen
• Clean the case with mild soap and water, avoiding the ventilation slots
• For yellowed plastic, see the Retrobrite page

Keyboard and Mouse Cleaning

• Remove keycaps for deep cleaning of Apple keyboards
• Clean mouse ball and rollers (if applicable)
• Wipe down surfaces with isopropyl alcohol

PRAM Battery Handling

The Performa 5400 uses a 4.5 V battery pack on a two-pin connector, not the half-AA lithium cell found in most Macintoshes of the period. Apple's Battery Replacement figure labels it a Rayovac computer clock battery, and the symptom charts for the closely related 6200/6300 print the step as "Unplug 4.5 V battery".

Reaching it means removing the I/O door and the logic board — it is not accessible from outside the chassis.

Apple's own check

1. Set the voltmeter to the 10 V DC scale.
2. Hold the positive probe to the positive end of the battery and the negative probe to the negative end.
3. If the battery voltage is below 3.0 V, replace the battery.

3.0 V is Apple's published threshold for this machine. Apple gives no replacement interval at all, so a fixed "every three to five years" is somebody's guess rather than a specification. Replace on measurement, or when the machine starts losing its date and startup-disk setting.

Cleaning Battery Leakage

The pack is alkaline, so vinegar is the correct neutraliser here. It is the wrong treatment on the lithium cells used by most other Macintoshes of the period.

• Remove the pack immediately if it has leaked
• Neutralise alkaline residue with white vinegar, then clean with isopropyl alcohol
• Inspect nearby traces under magnification and check continuity
• See Battery Explosion, Capacitor or Corrosion Damage for the full procedure

Connector and Socket Corrosion

Key Areas to Check

• RAM DIMM sockets – clean with DeoxIT and isopropyl alcohol
• PCI and expansion slot contacts
• Power connectors from PSU to logic board
• IDE and floppy drive ribbon cable connectors
• ADB and serial port connectors

Use DeoxIT D5 or similar contact cleaner for oxidized connections.

Common Failure Points

Power Supply

The power supply is a separate, orderable assembly from the analogue/video board — Apple lists 661-0930 (or 661-0331 with a thermal connector) for Rev. A and 661-1117 for Rev. B, with the analogue/video board assembly as 661-0928 (Rev. A) or 661-1356 (Rev. B). They are not one board and they are not interchangeable across revisions.

Symptoms that point at the supply rather than the analogue board:

• Dried or leaking electrolytic capacitors
• Failed solder joints on high-current paths
• A machine that will not start from the rear power switch at all (Apple's symptom chart sends "system does not start up" to a logic board reset, then the power supply)

Apple's chart sends a machine that will start from the rear switch but not from the keyboard to the analogue board, not the power supply — as it does a machine that restarts itself after Shut Down.

Capacitor Health

See the Macintosh Performa 5400 Capacitor Replacement Guide for detailed recapping information. Key symptoms of capacitor failure include:

• Distorted or absent audio
• Boot failures or instability
• Visual artifacts on display

CD-ROM Drive

The 5400 ships with a tray-loading AppleCD 600i, an AppleCD 1200i or a 12× drive depending on configuration.

• Clean the laser lens with isopropyl alcohol
• Apple's own remedy for a drive that will not read is to clean it and then replace the mechanism; there is no published component-level repair

CRT Issues

• Fading or dim display may indicate failing flyback transformer
• Geometric distortion can result from capacitor failure
• Color issues may be caused by failing neck board components

Logic Board Socket Oxidation

Check and clean:

• RAM slot contacts
• PCI and expansion slot contacts
• Processor socket (if removable on upgrade cards)

High-voltage adjustment

This chassis is one of the few Macintoshes for which Apple publishes a real voltage adjustment with a real tolerance. The 5400 shares its power supply and analogue/video board part numbers with the Performa 5200/5300, and the procedure is identical.

1. Let the monitor run for at least 10 minutes.
2. Run Display Service Utility and display the crosshatch test pattern.
3. Locate diode D713 (Rev. A) or D703 (Rev. B) on the analogue board.
4. Red voltmeter lead to the cathode of that diode; black lead to the metal chassis ground.
5. With a fine-tip plastic tool, set VR501 (Rev. A) or VR702 (Rev. B) until the meter reads 29.5 V DC ± 0.1 V.

Apple requires this adjustment whenever the CRT or the deflection board is replaced.

The geometry controls are on a different board — the CRT video board carries VR301 to VR305, VR601, VR701 and the three-position horizontal centring switch SW701, all reached from the neck of the tube. Do not confuse them with the high-voltage control.

Power supply specification

Apple's electrical specification:

• Line voltage: 100–240 VAC
• Frequency: 47–63 Hz
• Power: 125 W
• Surge voltage: 300 V RMS for 100 ms
• Peak inrush current: 40 A peak
• Current: 2.5 A maximum for all line and load conditions
• Power: 220 W maximum for all line and load conditions

The rail table "+5 V 4.85–5.15 V, +12 V 11.9–12.7 V, +3.3 V 3.2–3.4 V" does not belong to this machine. The first two lines are Apple's Macintosh Plus adjustment procedure — genuine there, with test cable 077-0135 and an upper bound of 12.75 V — transplanted onto machines that have no such procedure. No source of any kind has been found for the +3.3 V line. Apple publishes no per-rail tolerance and no power-supply adjustment for the 5400; the 29.5 V high-voltage adjustment above is the only one it documents.

Related Maintenance Pages

• Macintosh Performa 5400CD
• Macintosh Performa 5400 Troubleshooting
• Macintosh Performa 5400 Capacitor Replacement Guide
• CRT Discharge Procedure