IBM PS/2 Model 30 Troubleshooting Guide
Fault diagnosis for the IBM PS/2 Model 30 (machine type 8530) follows IBM's service procedure for the PS/2 models with an AT (ISA) bus. It applies to both the 8086 Model 30 and the Model 30 286, which differ in processor, video, clock and power supply; see the maintenance guide to tell them apart.
IBM's PS/2 Hardware Maintenance Manual gives one checkout procedure and symptom index for the Models 25, 25 SX, 25-286, 30, 30-286, 33, 35, 40 and 55, separate from the one for Micro Channel machines.[1] The tables below come from it.
Before you start
[edit | edit source]- Switch on with the Starter Diskette or Advanced Diagnostics diskette already in the drive. Warm-booting them with Ctrl-Alt-Del can give false errors and a false indication that a power-on password is set.[2]
- If POST shows several errors, deal with them in the order shown. The first can cause the others.[2]
- Run Advanced Diagnostics before replacing parts. If the diagnostics find nothing, replacing parts will probably not fix it.[2]
- On a Model 30 286, check that the voltage switch on the rear is set for the local mains.[1][3]
IBM's general checkout for these models: switch everything off, check the cables, remove any diskettes, switch on the external devices and then the computer. If a POST error appears, load Advanced Diagnostics and look for one or two short beeps and the IBM logo; if they do not appear, go to the symptom index. If the device list is wrong or a test fails, follow the diagnostics. If the tests pass but the fault is intermittent, check cables and connectors, reseat adapters, drives and modules, check the fan, and run the tests repeatedly with an error log.[1]
A successful POST ends with one short beep. After a noncritical error POST stops and shows the code; F1 continues.[3]
Dead system
[edit | edit source]Ardent Tool's summary of IBM's advice is that with no POST, a blank screen and no beep, the most likely cause is a device shorting the power supply: a badly inserted memory module or a faulty adapter or drive. The system board must return Power Good to the supply within 150 ms or the supply shuts itself down.[2]
| Symptom | IBM FRU order |
|---|---|
| No beep, power-on light off, fan not running | Power supply (check the voltage switch) |
| No beep during POST | System board, power supply, any adapter, bus adapter (check the voltage switch) |
| No beep, fan runs, light on, hangs during POST with a message | System board, power supply |
| No beep, computer otherwise works | Speaker |
Source: IBM PS/2 Hardware Maintenance Manual, p. 12.[1]
- Check the line cord at both ends. Loose or badly seated cords cause intermittent faults, including unexpected resets. Unplug it before working on its contacts.[2]
- Measure Power Good at P3 pin 1 with the machine switched on. It should read +3.5 to +5 V.[4]
- If it does not, remove all adapters, options, extra memory and external connections, then switch on and listen for a beep.[2][4]
- No beep: check the speaker; if it is good, replace the system-board memory and try again; if there is still no beep, measure the supply outputs. Correct outputs point to the system board, wrong ones to the supply.[2]
- A beep: refit the adapters and options one at a time. The item fitted just before the beep stops is the likely fault.[2]
Ardent Tool's list of common causes adds a memory module fitted backwards, an adapter not fully seated, an unsupported or faulty adapter, and too many drives spinning up at once on a heavily loaded machine.[2]
The supply outputs, the measurement limits and IBM's under-voltage sense levels are in the maintenance guide. A rail below its sense level (+4.5 V, −4.3 V, +10.8 V or −10.2 V) stops the supply raising Power Good, so POST never starts.[3][5]
Beep symptoms
[edit | edit source]| Symptom | IBM FRU order |
|---|---|
| One long and two short beeps | System board, display adapter |
| More than one beep during POST | System board, any adapter |
| Continuous beep | System board |
| Repeated short beeps | Keyboard (stuck key?), keyboard cable, system board |
Source: IBM PS/2 Hardware Maintenance Manual, p. 13.[1]
Numeric error codes
[edit | edit source]IBM's list for the AT-bus models, with the codes that apply to a Model 30:[1]
| Code | IBM action and FRU order |
|---|---|
| 1XX | System board |
| 161, 163, 165 | Set the time and date; bus adapter; clock module; battery; system board |
| 162 | Run Setup and Automatic Configuration; clock module; system board |
| 162, with Advanced Diagnostics unable to run | Diskette drive; system board; diskette drive cable |
| 164 | Run Setup and Automatic Configuration (check memory); system board |
| 199 | Any device |
| 2XX | System board (check memory) |
| 302 | Is the keylock locked? Keylock assembly; system board |
| 3XX | Keyboard; system board; keyboard cable |
| 5XX | System board; display adapter |
| 602 | System board; diskette drive; diskette drive cable |
| 604, 662 | Wrong diskette drive type |
| 663 | Wrong media type |
| 6XX | Diskette drive; external drive adapter; system board; power supply; diskette drive cable |
| 7XX | Math coprocessor; system board |
| 17XX | Hard disk drive; system board; hard disk cable; power supply |
| 2401, 2402 | If the screen colours change: display. If they do not: system board, then display |
| 2409 | Display |
| 2410 | System board; display |
| 86XX | Mouse; system board |
Codes are sometimes shown with more digits. Ardent Tool's reading of IBM's rule is to add two zeros on the right and pad with zeros on the left to eight characters, and to ignore the last four characters of a twelve-character message.[2]
Battery and clock codes
[edit | edit source]On the 8086 Model 30 the bus adapter in the 161 list is the riser card, which carries the clock's 3 V cell. On the Model 30 286 the clock module is a plug-in DS1287.[6][3] A weak battery loses all the setup information; if only part is lost, the battery is probably not the cause.[2] IBM notes that a clock losing time is not always a hardware fault, because the time-of-day count is interrupt-driven; check the time in the Starter Diskette's Set Features menu.[1] Battery replacement and the riser voltage check (retain tip H067282, replace the bus adapter below 2.5 V at pins 38 and 39) are in the maintenance guide.
Memory errors
[edit | edit source]The Model 30 has 128 KB soldered to the planar and 512 KB in two banks of modules.[5] IBM's memory procedure for the 8086 machines:[1]
- Parity Check 1 means system-board memory has failed. On an 8530 with 640 KB, if the address shown below the message is below 20000 (hex), replace the system board; otherwise replace modules S1 and S2.
- Parity Check 2 means memory on an adapter has failed.
- A 205 memory error on an 8530 means the system board.
- Other 20X errors appear as AAAAAA BB CCCC 20X; IBM's procedure uses the address and the BB and CCCC fields to choose between S1 and S2.
Other symptoms
[edit | edit source]| Symptom | IBM FRU order |
|---|---|
| Blank or unreadable display | System board; power supply; display adapter; system board video cable |
| Insert Diskette icon appears, or the system enters BASIC | Diskette drive; system board; diskette cable; network adapter |
| Bad Diskette icon | Diskette; diskette drive; system board; diskette cable |
| Incorrect memory size, or Parity Check 1 | System board (check memory) |
| Serial or parallel device failure | Device (does its self-test pass?); system board; bus adapter |
| Some or all keys do not work | Keyboard; system board; keyboard cable |
| Real-time clock loses time | Bus adapter; clock module; system board (not always a hardware fault) |
Source: IBM PS/2 Hardware Maintenance Manual, pp. 13–14.[1] With no bootable diskette or fixed disk, pressing F1 at the Insert Diskette icon starts Cassette BASIC. That is normal.[3]
Keyboard and mouse
[edit | edit source]On the 8086 Model 30 the keyboard and mouse can plug into either socket, because the interface logic is the same.[5] On the Model 30 286 the keyboard socket is marked "1" and the pointing device "2".[3]
Code 305 is a keyboard voltage error. IBM's order is the keyboard port fuse, the keyboard cable and the system board; if the system has no fuse, replace the system board.[2] Ardent Tool's planar maps list F1 and F2 as the probable mouse and keyboard fuses on the 8086 planar, and a single F1 on the 286 planar.[6][7]
Diskette drive
[edit | edit source]Codes 604 and 662 mean the wrong drive type and 663 the wrong media: check the drive and diskette before replacing anything.[1] A 1.44 MB drive has "1.44" on its eject button; a 720 KB drive cannot use 2 MB (1.44 MB) diskettes.[3]
For other 6XX codes, IBM's order is the drive, the external drive adapter, the system board, the power supply and the cable.[1] Before replacing the drive, check the common mechanical and electrical faults of PS/2 drives: dirt on the Mitsubishi head actuator spindle, a detached head-damper pad on ALPS drives, and leaking surface-mount capacitors on the drive board.[8] See IBM PS/2 Model 30 Capacitor Replacement Guide and Floppy Drive Repair.
The drive takes its power through the same cable as its signals, so check that the cable is aligned and seated at both ends.[9]
Fixed disk
[edit | edit source]IBM's order for 17XX codes is the drive, the system board, the cable and the power supply.[1] The Model 30's drive is not an ST-506 drive: its controller is built into the drive assembly, which connects to a dedicated interface on the planar.[5][9]
- On an 8530-001 or -021, check IBM retain tip H007157 before anything else. It requires particular combinations of system board, drive and Advanced Diagnostics version, and a drive formatted with the wrong version gives fixed-disk errors. The table is in the maintenance guide.[6]
- A drive that does not spin up after storage may be stuck by stiction. Peter Wendt describes freeing one by power cycling or by rotating the unplugged system unit sharply; back up the data at once if it works.[10]
- Park the heads with the Advanced Diagnostics diskette before removing a Model 30 286 drive.[3]
Display
[edit | edit source]For 2401 and 2402, watch the screen colours: if they change, suspect the display; if not, the system board.[1]
- An 8086 Model 30 connected to an 8515 or 8516 shows compressed, distorted video. IBM retain tip H094152 says these displays are not supported on the 8086 models.[6]
- On some 8530-001 and -021 machines, cursor keys that put wrong characters on the screen, or a 501 with two or more option cards fitted, come from gate arrays at U9 and U15 without "Japan" printed on them (retain tip H043664). IBM's fix was a new system board, FRU 64F3453.[6]
Power-on password
[edit | edit source]On the Model 30 286, the password override is the J13 jumper. Move it from pins 1–2 to pins 2–3, or from 2–3 to 1–2, and leave it in the new position until the next reset. Then set a new password from the Starter Diskette.[3][11]
IBM retain tip H036143 covers Model 30 286 machines shipped after 1 August 1989, on which a 4717 attached to the pointing-device port gives an 8602 error, because a planar change grounded pin 2 of that port. IBM's fix was interposer cable P/N 31F6759.[7]
Related pages
[edit | edit source]- IBM PS/2 Model 30
- IBM PS/2 Model 30 Maintenance Guide
- IBM PS/2 Model 30 Capacitor Replacement Guide
- IBM PS/2 Model 25 Troubleshooting Guide
- Capacitor Failure Symptoms
- Recommended Tools
References
[edit | edit source]- ↑ 1.00 1.01 1.02 1.03 1.04 1.05 1.06 1.07 1.08 1.09 1.10 1.11 1.12 IBM, IBM Personal System/2 Hardware Maintenance Manual, S52G-9971-02, October 1994. Hosted on this wiki as IBM Personal System 2 Hardware Maintenance Manual (S52G-9971-02, October 1994) (PDF). "General Checkout (AT Bus)", pp. 3–5; "Memory Problems (8086 Computers)", pp. 6–8; "Symptom-to-FRU Index (AT Bus)": no-beep symptoms, p. 12, beep symptoms and miscellaneous symptoms, pp. 13–14, numeric error codes, pp. 15–18; "Real-Time Clock Problems", p. 150.
- ↑ 2.00 2.01 2.02 2.03 2.04 2.05 2.06 2.07 2.08 2.09 2.10 2.11 "PS/2 Error Codes", Ardent Tool of Capitalism, with the tables for 160–199 and 300–999. The warm-boot warning; resolving multiple POST errors in the order shown; running Advanced Diagnostics before replacing parts; the dead-system procedure (a shorting device as the most likely cause, Power Good within 150 ms, line-cord checks); the battery note; code 305 ("If no fuse in system replace system board").
- ↑ 3.0 3.1 3.2 3.3 3.4 3.5 3.6 3.7 3.8 IBM, IBM PS/2 Model 30 286 Hardware Maintenance Reference, S64F-3988-00, March 1990. Hosted on this wiki as IBM PS2 Model 30 286 Hardware Maintenance Reference (PDF). Sections 1.1.2 (power-on password and J13), 1.2.6 (keyboard and pointing-device connectors), 3.1 (power supply switch and under-voltage sense levels), 3.2 (POST: one short beep, critical and noncritical errors, Insert Diskette icon, Cassette BASIC), 6.3 (park the heads before removing a fixed disk).
- ↑ 4.0 4.1 Louis Ohland, Tomáš Slavotínek et al., "8525 / 8530 Power", Ardent Tool of Capitalism. P3/P4 measurement limits for the Model 30 and 30-286, the minimum under-voltage sense levels, and the Power Good check (+3.5 to +5 V with the system running; otherwise remove adapters, cables and extra memory and refit them one at a time).
- ↑ 5.0 5.1 5.2 5.3 IBM, IBM Personal System/2 Model 30 Technical Reference, January 1987. Hosted on this wiki as IBM PS2 Model 30 Technical Reference (January 1987) (PDF). Keyboard and pointing device controller, p. 1-9; read/write memory, p. 1-22; fixed disk connector, pp. 1-106 and 1-107; Section 3, "Power Supply", pp. 3-3 to 3-6.
- ↑ 6.0 6.1 6.2 6.3 6.4 Louis Ohland, Tomáš Slavotínek et al., "8530 Planar (8086)", Ardent Tool of Capitalism. The MM58167AN clock at U16; riser card P/N 61X8864 and 61X8910 with the B1 BR-2/3A cell; F1 and F2 as probable mouse and keyboard fuses; and the text of IBM retain tips H007157, H043664, H067282 and H094152.
- ↑ 7.0 7.1 Louis Ohland, Tomáš Slavotínek et al., "8530 286 Planar", Ardent Tool of Capitalism. F1 fuse, J13 password override, ZM35 DS1287, and IBM retain tip H036143.
- ↑ "60, 65 SX, and 80 – Common Devices", Ardent Tool of Capitalism. Peter Wendt on ALPS and Mitsubishi PS/2 diskette drives: dust through the unshielded slot, dirt on the Mitsubishi 355 head actuator spindle, ALPS drives losing the head-damper pad, and Mitsubishi capacitors causing 6xx errors.
- ↑ 9.0 9.1 "IBM PS/2 Model 30", DOS Days. Drive power through a proprietary fitting with no Molex connectors; the fixed-disk interface is neither ESDI nor standard MFM.
- ↑ "Known Problems – Experience, RETAIN Tips, ECAs", Ardent Tool of Capitalism. Peter Wendt on hard-disk stiction.
- ↑ IBM, Personal System/2 Model 30 286 Guide to Operations, first edition, September 1988. Hosted on this wiki as IBM PS2 Model 30 286 Guide to Operations (PDF). "Power-on Password Reset", pp. 3-4 and 3-5.