Amstrad PC2286 Maintenance Guide
Amstrad's service manual for the Amstrad PC2286 is held by the Centre for Computing History but has not been made available to owners, so the procedures below come from owners' repairs and from the PC2386's service manual, whose power supply parts list matches the PC2286 supply that one owner documented. The machine has its own fan-cooled supply in the system unit, BIOS settings kept by AA cells, and a main board made of two boards plugged together.[1][2]
Safety
[edit | edit source]Warning: the supply runs from the mains and its large reservoir capacitor stays charged after unplugging. An owner measured more than 200 V across it with the supply powered.[1] On the PC2386, whose supply matches, this capacitor is C601, 330 µF 400 V.[2] Discharge it before touching the board, and check the monitor separately; see CRT Discharge Procedure.
Opening the case and the two boards
[edit | edit source]The ISA slots are on an expansion board plugged into the main board below it. One owner who had taken the boards out found that the machine would not start until both boards had been refitted in the case and the expansion board properly seated; the expansion board flexes when unsupported on a bench and its connectors to the main board do not hold it.[1] Test the boards installed in the case.
Backup cells
[edit | edit source]Four AA cells under the monitor keep the BIOS settings.[3] Remove old cells and clean any leakage from the holder; on the PC1640, cells in the same position leaked down onto the main board.[4] After fitting new cells, enter the hard disc type in the BIOS; one owner's 40 MB drive is type 1.[5] See Battery Explosion, Capacitor or Corrosion Damage.
Power supply
[edit | edit source]The supply plugs into the main board through an eight-pin connector. One owner gives its pins as:[1]
| Pin | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 |
|---|---|---|---|---|---|---|---|---|
| Rail | +5 V | −5 V | +5 V | −12 V | 0 V | +12 V | 0 V | 0 V |
With this pinout the main board can be tested from an AT or ATX supply while the original is repaired.[1] The PC2386's alignment, which uses the same supply parts, sets +5 V to 5.00 V ±0.05 V with VR604 at test point A and +12 V to 12.00 V ±0.05 V with VR603 at test point B, and sets the primary protection by turning VR601 anticlockwise until it starts to cut in, then back a little; check that the presets on a PC2286 board carry the same numbers before using them.[2]
The supply fan is a 60 × 25 mm 12 V unit; owners fit a quieter modern fan.[1] On a machine stored in a damp, unheated place the supply board was corroded, with broken tracks; the owner washed the corrosion off with water, washing-up liquid and a toothbrush, let the board dry, and then traced and repaired the broken tracks.[1]
Memory
[edit | edit source]The main memory is in socketed TMS44C256-12N DRAMs, with SIMM sockets as an alternative. One owner cured a black screen by removing the DRAM chips and fitting two 1 MB 30-pin SIMMs, after setting the memory jumpers for SIMMs. The board does not take DRAM chips and SIMMs at the same time, and owners warn that three-chip SIMMs may not work.[1][5] One owner has fitted the 80286's maximum of 16 MB, and with the MEMM.SYS driver from the system discs the board's LIM EMS hardware makes it available as expanded memory.[1]
Keyboard
[edit | edit source]The keyboard uses Amstrad's own interface. One owner cured a "check keyboard" fault by refitting a Caps Lock LED that had come loose inside the keyboard and cleaning the pressure-pad sheet and its ribbon edge connectors.[6] Another fault of the same kind was on the main board; see the Amstrad PC2286 Troubleshooting Guide.
Related pages
[edit | edit source]- Amstrad PC2286 · Amstrad PC2286 Troubleshooting Guide · Amstrad PC2286 Capacitor Replacement Guide
- Amstrad PC2386 Maintenance Guide · Amstrad PC2086 Maintenance Guide
- Hard Drive Maintenance and Repair · Recommended Tools
References
[edit | edit source]- ↑ 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 VintageVic, acgs, GiGaBiTe, mR_Slug and others, "Amstrad PC 2286", Vintage Computer Federation Forums, April–October 2022. Retrieved 2026-10-02. Community repair thread: supply parts, fan, main board power connector, two-board assembly and its seating, DRAM and SIMM memory, LIM EMS, disabling the built-in VGA, corrosion after damp storage.
- ↑ 2.0 2.1 2.2 Amstrad plc, PC2386-65 Personal Computer Service Manual. Hosted as File:Amstrad PC 2386 Service Manual.pdf, described at Amstrad PC 2386 Service Manual. Safety tests p. 2; alignment instructions p. 3; electrical parts list pp. 44–45.
- ↑ Centre for Computing History, "Amstrad PC2286/40", exhibit CH1264. Retrieved 2026-10-02. The CMOS backed by four AA cells under the monitor.
- ↑ Wobblestone, "Amstrad 1640 (germany: Schneider PC 1640) with battery damage", Vintage Computer Federation Forums, November 2024. Retrieved 2026-10-02. Community report of AA cell leakage reaching a PC1640 main board.
- ↑ 5.0 5.1 VintageVic, "Fixing Amstrad PC2286 with black screen and keyboard issues", Vintage Computer Federation Forums, January 2026. Retrieved 2026-10-02. Community repair: DRAMs replaced by two 1 MB SIMMs with the jumpers changed, keyboard error cured by replacing electrolytics C403–C406, C408 and C409 near the keyboard connector, the 40 MB drive set as type 1.
- ↑ pearce_jj and others, "Amstrad PC2286 'Check Keyboard'", Vintage Computer Federation Forums, September 2010. Retrieved 2026-10-02. Community repair: a PC2286 stuck on "check keyboard", the key lock changing the beep rate, the fault cured by refitting a loose Caps Lock LED inside the keyboard and cleaning the pressure-pad sheet and its connectors; John Elliott on Amstrad's proprietary keyboard interfaces.