Macintosh LC 475 Capacitor Replacement Guide

Recapping the Macintosh LC 475 and its identical twin the Quadra 605 is straightforward by the standards of this family: eleven surface-mount electrolytics, all on the top side of the board, and no silkscreen traps.

The logic board is 820-0364-A (1993). It is a different board from the LC III, with a different capacitor complement, so the two lists are not interchangeable. The same board is used by the Macintosh Performa 475/476.

Tools, removal and fitting procedure, power supply data and battery information are common to the whole "pizza box" family and live on Macintosh LC Capacitor Replacement Guide. This page carries what is specific to the LC 475.

Symptoms of capacitor failure

The same pattern as the rest of the family — sound loss first, then intermittent starting, then visible residue and corroded copper — but generally less advanced, because these boards are two to three years younger than the LC and LC II and use fewer, larger capacitors. That is a difference of degree, not of kind: an unrecapped 820-0364 board in 2026 still needs doing.

Unlike the LC III, the LC 475's bulk capacitor on the −5 V rail is wired the correct way round, so an LC 475 with serial port faults after a recap is a genuine fault rather than the LC III's known silkscreen error.

See Macintosh LC Capacitor Replacement Guide for the full symptom list and Capacitor Failure Symptoms for the general picture.

Macintosh LC 475 / Quadra 605 logic board (820-0364-A)

Eleven surface-mount electrolytic capacitors:

• 9 × 47 µF 16 V
• 2 × 100 µF 6.3 V

Macintosh LC 475 / Quadra 605 logic board 820-0364-A. Each capacitor is marked with its value, working voltage and positive terminal. Source: Recap-a-Mac.

On sourcing: these figures come from a single community source, Recap-a-Mac's annotated photograph of an 820-0364-A board. Unlike the LC, LC II and LC III boards, this one has no second published list to cross-check against — Console5 does not carry an LC 475 entry, and Apple never published component-level data for any Macintosh of this era. The photograph is therefore both the value list and the location map: work from it rather than from a designator table, and read the value printed on each capacitor body before you lift it.

Power supply and battery

Shared with the rest of the family: Apple power supply 661-1733, a universal 100–240 VAC auto-ranging switch-mode unit, and lithium battery 742-0011. The supply exists in six known vendor variants with different capacitor complements — identify yours by its label before ordering. Full data on Macintosh LC Capacitor Replacement Guide.

Apple rates the Quadra 605 at 26 W maximum, monitor excluded, and gives its mains frequency range as 50–60 Hz against 47–63 Hz for the rest of the LC series.

The PRAM battery, and the CR2032 question

Apple's part is a 3.6 V lithium half-AA, part number 742-0011, in a clip-in holder. Apple's service check is to measure it on the 10 V DC range and replace it if it reads below 3.0 V.

Fitting a CR2032 holder in place of the original is a popular modification, because CR2032 cells are cheap and available everywhere. Be clear about the trade-off before you do it: a CR2032 is a nominal 3.0 V cell, which is exactly the voltage at which Apple's own procedure says to throw the battery away. A fresh CR2032 starts life at Apple's replace-now threshold and falls from there, so expect a shorter useful life and, on a machine that is marginal, PRAM that does not hold. A 3.6 V lithium half-AA in a holder — rather than a soldered-in cell — gives the original voltage with the same convenience.

Whatever you fit, fit it in a holder and take it out when the machine goes into storage. See Battery Explosion, Capacitor or Corrosion Damage and Battery Refurbishment.

Working around the processor

The 68LC040 is socketed. Apple's own upgrade procedure for the LC 475 and Quadra 605 removes it from the logic board with a dedicated processor removal tool, which Apple sells as a separate service part. Levering a PGA processor out with a screwdriver bends pins and cracks board corners; if you take it out to get at the board, use the proper tool or leave it in place.

Things that are not faults

• No FPU. The 68LC040 has no floating-point unit. Software that requires one will refuse to run on

 a standard LC 475 or Quadra 605. Apple's specification confirms the 68LC040 fitting.

• Two VRAM SIMMs. Apple ships the LC 475 and Quadra 605 with two 256 K VRAM SIMMs, upgradable

 to 1 MB — a pair of small modules in the sockets is the factory configuration, not a
 bodge.

• The PDS will not take an accelerator. Apple states that the 114-pin slot accepts LC-compatible

 I/O, display, network and video capture cards but does not support 030 processor accelerator or
 cache cards.

Related pages

• Macintosh LC 475
• Macintosh Quadra 605
• Macintosh LC 475 General Maintenance
• Macintosh LC 475 Troubleshooting
• Macintosh LC Capacitor Replacement Guide — shared procedure, power supply and battery
• Macintosh LC Series/ Quadra 605 Service Source