IBM PS/2 Model 60 Troubleshooting Guide
This guide documents fault diagnosis for the IBM PS/2 Model 60 (machine type 8560, submodels -041 and -071). The Model 60 shares the bulk of its POST architecture with the IBM PS/2 Model 50 but has tower-chassis-specific failure modes, ST-506 vs ESDI-specific error families and a different PSU.
Reference Diskette and Diagnostics
[edit | edit source]The Model 60 requires the Model 60-specific Reference Diskette (covers both the 8560-041 and the 8560-071). Reference Diskettes are not cross-compatible between PS/2 submodels; the wrong Reference Diskette will refuse to run or will mis-configure the planar.
Boot Options:
- F1 — boot the Reference Diskette (Set Configuration, Set Features, Display Configuration, Copy Option Diskette, Run Auto Configuration).
- Ctrl-A from the Reference Diskette menu — Advanced Diagnostics. The Advanced Diagnostics image is loaded into RAM from the Reference Diskette; the diskette can be removed once it loads.
If the Reference Diskette will not boot:
- Verify it is the Model 60 Reference Diskette (not Model 50 or 70/80).
- Verify it is a 1.44 MB DSHD diskette in good condition.
- Try a known-good Reference Diskette downloaded from Ardent Tool / PS/2 Museum archives.
POST Sequence
[edit | edit source]The Model 60 POST runs in this order:
- Reset; CPU register check.
- ROM checksum.
- CMOS / RTC battery check.
- Planar RAM count (with one beep at 640 KB).
- Floppy controller and drive seek.
- MCA adapter ID scan (each card returns a 16-bit ID).
- ADF lookup against CMOS configuration record.
- Hard disk controller initialisation.
- Boot device selection.
A four-digit numeric code displayed top-left on the screen is a fault code from the test block currently running. The code is the FRU lookup key.
Beep Codes
[edit | edit source]| Beeps | Meaning |
|---|---|
| 1 short | POST passed; normal boot. |
| 2 short | Configuration error; numeric error on screen. |
| 1 long, 1 short | Planar fault. |
| 1 long, 2 short | Display adapter fault. |
| Continuous | Power supply or planar fault. |
| None, no display | Planar or PSU fault before video init. |
Numeric POST Codes
[edit | edit source]POST codes follow the IBM convention where the test block is the leading digit(s).
1xx — Planar / System Board
[edit | edit source]| Code | Meaning | Notes |
|---|---|---|
| 101 | Interrupt failure | Planar IRQ controller fault. |
| 102 | Timer failure | 8254 timer (or its planar equivalent). |
| 103 | Timer IRQ failure | |
| 104 | Protected-mode failure | 80286 protected mode test failed. |
| 105 | Keyboard controller failure | Planar 8042-equivalent. |
| 106 | Logic gate / planar logic failure | |
| 107 | NMI failure | |
| 108 | Timer-bus timeout | |
| 109 | DMA test failure | |
| 110 | Planar parity check 0 | |
| 111 | I/O parity check | |
| 112 | Watchdog timeout | |
| 113 | DMA arbitration timeout | |
| 121 | Unexpected hardware interrupt | |
| 131 | Cassette wrap test failure | Vestigial — no cassette on PS/2; software-only check. |
| 161 | CMOS configuration empty | Dead RTC battery; replace MC146818+external pack (early planar) or DS12887 module (late planar). See IBM PS/2 Model 60 Maintenance Guide. |
| 162 | CMOS checksum bad | Same family as 161; often present together. |
| 163 | Time and date not set | Same family as 161. |
| 164 | Memory size mis-match with CMOS | Run SETUP from Reference Diskette. |
| 165 | MCA adapter ID mismatch | An MCA card's ID does not match the saved configuration. Run Auto Configuration. See "MCA-Specific Faults" below. |
| 166 | MCA arbitration failure | |
| 167 | Real-time clock failure | RTC chip itself (not just the cell). |
2xx — RAM
[edit | edit source]| Code | Meaning |
|---|---|
| 201 | Memory test failed (planar or memory adapter card) |
| 202 | Memory address line error |
| 203 | Memory address line error |
| 215 | Memory option-adapter failure (e.g., MCA Memory Adapter) |
| 216 | Memory option-adapter address conflict |
| 225 | Wrong memory speed for board (rare on Model 60) |
The 201 number is followed by the failed memory block address (8 hex digits). Use the address to identify the failing SIMM bank or MCA memory adapter slot.
3xx — Keyboard
[edit | edit source]| Code | Meaning | |
|---|---|---|
| 301 | Keyboard not responding | Wrong port? PS/2 mouse and keyboard ports are not interchangeable. Try a known-good keyboard. |
| 302 | User-indicated keyboard error | |
| 303 | Keyboard / system unit interface fault | |
| 304 | Keyboard or system unit interface failed | |
| 305 | +5 V fuse on planar (keyboard fuse) | Often blown by hot-plugging the keyboard. Replace fuse. |
| 365 | Keyboard mouse problem (PS/2 ports) |
6xx — Floppy Drive
[edit | edit source]| Code | Meaning |
|---|---|
| 601 | Floppy / drive failure |
| 602 | Floppy drive boot record failure |
| 604 | Floppy diagnostic error |
| 611 | Floppy adapter / controller failure |
| 613 | Cable / drive A: failure |
| 621 | Drive seek failed |
| 622 | Drive CRC error |
| 624 | Floppy data bus addressing error |
| 626 | Floppy data compare error |
8xx — Math Coprocessor
[edit | edit source]The Model 60 supports an optional 80287 coprocessor in the planar socket. The 80287 socket is on the planar near the 80286.
| Code | Meaning |
|---|---|
| 801 | Coprocessor test failed |
17xx — Fixed Disk Adapter / ST-506 (8560-041)
[edit | edit source]The 8560-041 uses the IBM Fixed Disk Adapter/A for its 44 MB ST-506 drive.
| Code | Meaning |
|---|---|
| 1701 | Fixed disk POST failure |
| 1702 | Fixed disk adapter failure |
| 1703 | Fixed disk drive failure |
| 1704 | Fixed disk adapter or drive failure |
| 1710 | Drive 0 read failure |
| 1711 | Drive 0 not ready |
| 1712 | Drive 0 random seek failure |
| 1713 | Drive 0 data compare failure |
| 1714 | Drive 0 controller test failure |
| 1730 | Drive 1 (any of the above) |
| 1780 | Drive 0 boot failure |
| 1781 | Drive 1 boot failure |
| 1782 | Disk controller failure |
A 17xx error on a working PS/2 ST-506 setup is usually one of:
- CMOS has the wrong drive type (run SETUP).
- IBM Fixed Disk Adapter/A capacitors aged (recap, see IBM PS/2 Model 60 Capacitor Replacement Guide).
- Single-cable interface intermittent (clean / reseat).
- Drive stiction (drive does not spin up).
104xx — ESDI Fixed Disk Adapter/A (8560-071)
[edit | edit source]The 8560-071 uses the IBM ESDI Fixed Disk Adapter/A for its 70 MB ESDI drive. The 104xx error family is unique to PS/2 ESDI controllers.
| Code | Meaning | |
|---|---|---|
| 10450 | Read/write test failure | |
| 10451 | Read verification failure | |
| 10452 | Seek failure | |
| 10453 | Wrong device type indicated | |
| 10454 | Controller buffer test failure | |
| 10455 | Controller failure | Often recoverable by recapping controller card. Don't discard the card on first 10455. |
| 10456 | Controller diagnostic failure | |
| 10461 | Format failure | |
| 10462 | Read failure (controller-side) | |
| 10463 | Write/read sector error | Recap controller card before condemning. |
| 10464 | Primary boot record read failure | |
| 10465 | ECC 8-bit error | |
| 10466 | ECC 16-bit error | |
| 10467 | Soft seek error | |
| 10468 | Hard seek error | |
| 10469 | Soft seek error count exceeded | |
| 10470 | Drive timeout | |
| 10471 | Drive busy | |
| 10472 | Status error after read/write | |
| 10473 | Read verify error | |
| 10480 | Drive 0 fatal error | |
| 10481 | Drive 1 fatal error | |
| 10482 | Controller failure | |
| 10483 | Reset failure | |
| 10484 | Drive head select failure | |
| 10485 | Drive size address error | |
| 10486 | Drive read capacity error | |
| 10487 | Drive volume initialisation error | |
| 10488 | Drive sector verify failure | |
| 10489 | Drive bad block table failure | |
| 10490 | Drive defective sector list failure | |
| 10491 | User-indicated drive read failure | |
| 10492 | User-indicated drive write failure | |
| 10493 | User-indicated controller failure | |
| 10499 | Controller failure |
Differentiating 1xxx (ST-506) vs 104xx (ESDI) is helpful when a previous owner has swapped the controller card.
Display POST Codes
[edit | edit source]| Code | Meaning |
|---|---|
| 401 | MDA (rare; not stock on Model 60) |
| 501 | CGA (not stock on Model 60) |
| 2401 / 2402 | Onboard VGA (planar) failure |
| 24xx | VGA video memory or VGA controller failure |
The Model 60 has onboard VGA on the planar. The VGA output is the 15-pin Mini-D-Sub on the planar bracket. A 24xx error is a planar / VGA fault.
MCA-Specific Faults
[edit | edit source]165 Card-ID Mismatch
[edit | edit source]By far the most common Model 60 fault for new restorers. The MCA card ID stored in CMOS does not match the actual cards now plugged into the riser. Causes:
- Card was added or removed without running Auto Configuration.
- MCA edge contact oxidation makes the card "disappear" from the bus on POST.
- RTC battery died and CMOS lost the configuration record (cluster with 161/162/163).
- CMOS battery is fine but the saved configuration was corrupted.
Fix:
- Boot the Reference Diskette.
- Select Set Configuration → Run Auto Configuration.
- If a card's ADF is not on the Reference Diskette, insert that card's option diskette when prompted. The ADF is copied to the working Reference Diskette.
- Save and reboot.
If 165 persists after Auto Configuration:
- Reseat every MCA card. Clean edge fingers with eraser and contact cleaner. MCA contacts oxidise badly after 30+ years.
- Try removing all cards, run Auto Configuration with bare planar, then reinstall cards one at a time.
- If one specific card causes the 165, recap the card.
ADF File Naming
[edit | edit source]ADF files are named @xxxx.ADF where xxxx is the four-hex-digit card ID. The Reference Diskette's Copy Option Diskette utility copies ADFs from option diskettes into the working Reference Diskette.
POST 17xx + 165 Together
[edit | edit source]This combination means: CMOS lost its configuration record (165) and the hard drive type is therefore "0" (none) (17xx). Run Auto Configuration, set the correct drive type, save and reboot. If the CMOS will not retain the configuration, the RTC battery is dead — replace.
ECA Recalls and Service Bulletins
[edit | edit source]The Model 60 was affected by several Engineering Change Authorisation (ECA) bulletins:
- ECA 087 — Reference Diskette compatibility update for newer MCA cards (apply by booting the updated Reference Diskette and running Set Configuration).
- ECA 092 — Planar fix for one revision of the Model 60 with an erratic +12 V regulator.
- ECA 117 — ESDI controller firmware update.
These ECAs apply only to specific FRU part numbers; check the planar / card FRU against the bulletin before applying.
PSU Faults
[edit | edit source]Symptoms and diagnosis:
- Dead — no fans, no power: Bulk capacitor or mains rectifier; verify mains; check chassis fuse if fitted; PSU recap required. See IBM PS/2 Model 60 Capacitor Replacement Guide.
- Fans spin briefly, then click-retry: Power Good not asserted in 150 ms. Could be PSU fold-back or shorted planar tantalum.
- Boots cold, fails when warm: Secondary electrolytics aged. Recap.
- Audible whine, smell of fish: RIFA X2 cap is venting. Stop using the system until X2 cap is replaced.
- Rails low/high: PSU feedback path issue. Recap and retest.
The 207 W PSU on the 8560-041 has less headroom than the 225 W PSU on the 8560-071. Rail sag under load on the 207 W PSU is more common.
Drive Stiction
[edit | edit source]ST-506 and ESDI drives in PS/2 service are prone to spindle stiction after long storage. Symptoms:
- Drive does not spin up. Faint "thunk" on power-on but no rotation.
- 1701/1711 (ST-506) or 10450/10470 (ESDI) at POST.
Field fix (works ONCE only, for data recovery):
- Power off.
- Open the chassis. Locate the drive.
- Gently rotate the drive case 45–90° around its spindle axis in both directions to free the heads.
- Re-install. Power on.
After the drive boots, immediately image its contents to a modern disk image file. The drive cannot be trusted to spin up reliably again. Replace it with a known-good period drive or with an XT-IDE / SCSI substitute via a converter board.
Floppy Faults
[edit | edit source]Symptoms and resolution:
- 601 / 602 / 604: Drive belt slipped, head dirty, or drive logic board capacitor failure. See IBM PS/2 Model 60 Maintenance Guide.
- 611 / 613: Single-cable issue. Reseat / clean cable. Verify pin 1 orientation.
- Continuous activity light, no read: Cable on backwards. Power off immediately.
Keyboard / Mouse Faults
[edit | edit source]- 301: Keyboard or mouse in the wrong port. The two Mini-DIN-6 ports look identical but are wired differently. Mouse in keyboard port → 301.
- 305: +5 V fuse on planar blown. Replace 3 A fuse.
- 365: PS/2 mouse fault. Try a known-good mouse before suspecting the planar.
Memory Faults
[edit | edit source]- 201 with address in the on-planar range: SIMM (planar memory) failure. Identify failing bank from the address. Note: the Model 60 uses IBM proprietary 30-pin-like 72-pin SIMMs that are not standard PC SIMMs.
- 201 with address in an MCA memory adapter range: Memory adapter card failure. Reseat or recap.
- 215 / 216: MCA Memory Adapter configuration error. Run Auto Configuration.
Boot Failures
[edit | edit source]If the system POSTs but will not boot:
- Verify drive type in CMOS via SETUP.
- Verify boot record on the hard drive (boot from Reference Diskette and run DISK FORMAT only if you have a backup).
- If 8560-041 ST-506 drive will not boot but POST passes, the partition table or boot sector is corrupt.
When to Suspect the Planar
[edit | edit source]- 1xx errors that persist after CMOS battery replacement and Auto Configuration.
- 10x errors with no other peripheral fault visible.
- No video and no beeps after PSU verified known-good.
- Repeated 165 errors after every card removed and reseated and a full Auto Config done.
A failed planar capacitor (10 µF / 16 V tantalum) is the most common Model 60 planar failure. See IBM PS/2 Model 60 Capacitor Replacement Guide.
Diagnostic Workflow
[edit | edit source]- Power on. Listen for beep.
- Note POST screen — any leading numeric code.
- If 161/162/163 cluster — replace RTC battery (or DS12887 module on late planar).
- If 165 — run Auto Configuration; if persists, clean MCA contacts.
- If 17xx (ST-506) / 104xx (ESDI) — verify drive type in CMOS; reseat drive cable; consider stiction; consider controller cap failure.
- If 24xx — planar VGA fault.
- If no beep and no video — PSU first (rail check), then planar tantalum check.
- Run Advanced Diagnostics (Ctrl-A) once basic POST passes.
Related Pages
[edit | edit source]- IBM PS/2 Model 60
- IBM PS/2 Model 60 Maintenance Guide
- IBM PS/2 Model 60 Capacitor Replacement Guide
- IBM PS/2 Model 50 Troubleshooting Guide — desktop sibling, same POST family
- IBM PS/2 Model 80 Troubleshooting Guide — same tower chassis
References
[edit | edit source]- PS/2 Error Codes — Ardent Tool of Capitalism. Source for the 1xx–104xx error code tables.
- IBM PS/2 Model 60 — Ardent Tool Quick Reference (IBM GJAN-43VS3S). FRU data and ECA history.
- IBM, IBM Personal System/2 Hardware Maintenance Manual (S52G-9971-02, October 1994). POST error code reference.