Macintosh Performa 275 Troubleshooting
The Macintosh Performa 275 is the Macintosh Color Classic II sold under a Performa name, and Apple covers both in the same service manual.[1][2] The fuller guide is Macintosh Color Classic II Troubleshooting; the table below gives Apple's own first steps from the Macintosh Color Classic II/Performa 275 Service Source, with cures in Apple's order of likelihood.
Mains voltage and the CRT's stored charge are present inside this machine. Discharge the CRT before touching the analogue board or the tube; see CRT Discharge Procedure.
Apple's symptom charts
[edit | edit source]| Symptom | Apple's cures, in order |
|---|---|
| No video, no sound, no drive activity | Connect the power cord; switch on; replace the power cord; replace the analogue board; replace the logic board (p. 33) |
| Screen black, too dark or too bright; sound and drive work | Adjust the contrast button; adjust brightness in the Brightness control panel; check the yoke cable; perform the video adjustments; replace the analogue board; replace the CRT (p. 19) |
| Screen bright with sound, but no picture | Perform the video adjustments; replace the analogue board; replace the CRT (p. 19) |
| Clicking, chirping or thumping | Check the logic board power cable at J12; replace the analogue board; replace the logic board (p. 33) |
| Smoke or smell | Replace the analogue board (p. 33) |
| Sad Mac icon | Try a known-good disk; replace the RAM SIMMs; replace the logic board (p. 34) |
| Hard drive does not work | Remove any SCSI loopback card; check the internal drive has all three terminating resistor packs; check external termination; replace the drive; replace the logic board; replace the data cable (p. 29) |
Apple's charts stop at module level. On a machine this age, leaking capacitors on the logic board and the analogue board, and a leaking PRAM battery, are the first suspects.
Notes
[edit | edit source]Apple's technical specifications give the Performa 275 one 72-pin SIMM socket and 36 MB maximum; the Service Source prints the Color Classic's two 30-pin sockets. Check the board before buying memory.[3]
Apple's battery rule is to replace the cell below 3.0 V (PDF p. 91).[2] Neutralise lithium battery leakage with sodium bicarbonate, not vinegar. See Battery Explosion, Capacitor or Corrosion Damage.
A Sad Mac icon shows a code that identifies the failing test; decode it with Sad Mac Error Codes.
Related pages
[edit | edit source]- Macintosh Performa 275
- Macintosh Color Classic II Troubleshooting
- Macintosh Color Classic II General Maintenance
- Macintosh Color Classic II Capacitor Replacement Guide
- Sad Mac Error Codes
References
[edit | edit source]- ↑ Low End Mac, "Apple's Performa Line, 1992 to 1997".
- ↑ 2.0 2.1 Apple Computer, Service Source: Macintosh Color Classic II/Performa 275, Troubleshooting, PDF pp. 18–34, File:Color classic ii.perf 275.pdf; see Macintosh Color Classic II/ Performa 275 Service Source.
- ↑ Apple, "Macintosh Performa 275: Technical Specifications".