Apple Studio Display 21 Troubleshooting Guide
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Fault-finding on the Apple Studio Display 21, following Apple's symptom charts. Apple's note at the head of the charts is to let the display warm up for about 30 minutes before any procedure that needs it switched on.[1] The procedures it refers to are in Apple Studio Display 21 General Maintenance. Read CRT Discharge Procedure before opening the display.
First checks
[edit | edit source]- The display is approved for USB-based 1999 Power Macintosh G3 and Power Mac G4 computers. Its geometry and colour controls work through USB and the Apple Displays Software, so both the video and USB cables must be connected.[1]
- With an Apple video card, connect through the VGA-to-Macintosh adapter (922-3769) to the card's DB-15 port, adapter first; the extra geometry and colour controls depend on signals that are missing from the VGA-style connectors of most third-party cards.[1]
- Colour patches or brightness changes in one area often come from magnetised metal furniture. Move the display; if the symptom changes, the location is the cause. Small colour imperfections are within CRT tolerance and can be reduced with beam landing, rotation, brightness or contrast.[1]
Symptom charts
[edit | edit source]| Symptom | Cures in Apple's order | Service Source page |
|---|---|---|
| No video, power light off | 1. Shut down; check the power cord for damage and continuity. 2. Check it is plugged into the back of the computer, that the computer is on and that the display's power button is on. 3. Check fuse FP1 on the power board; replace a blown fuse with 4 A 250 V (922-0502). If the new fuse blows, replace the power board; if it blows again, refit the original power board with a new fuse and replace the main deflection board, the likely cause. 4. Reseat the user controls board and its connectors. 5. Replace the user controls board. | Troubleshooting 4 |
| No video, power light amber | 1. Check the cables for bent pins; both USB and video cables must go to the computer. 2. Try a known-good monitor on the computer. 3. Check the internal cables to the CRT/video board. 4. Replace the main deflection board and adjust. 5. Replace the power board. 6. Replace the video cable. 7. Download the set-up parameters (with a second monitor if needed) and replace the CRT/video board. | 4-5 |
| No video, power light green | 1. Check brightness and contrast are not at minimum. 2. Check the video and USB cables. 3. Check that single-pin connector B104 on the CRT/video board is seated. 4. Check both pins of BL1 (red and black yoke wires to the main deflection board). 5. Check the high voltage; if it is 0 V, replace the main deflection board. 6. Download the set-up parameters and replace the CRT/video board. | 5 |
| Raster distorted | 1. Read the first checklist. 2. Degauss by switching everything off for 20 minutes. 3. Turn the display at least 90° or move it; if the symptom changes, the cause is a stray field. 4. Click Factory Settings under Geometry in the Monitors control panel. 5. Adjust the geometry controls. 6. Replace the main deflection board. | 5 |
| Screen one predominant colour | 1. Check the video cable and adapter for damaged or missing pins. 2. Check internal connectors for bent pins. 3. Choose a standard white point (D50, 6500 or 9300) and click Recalibrate. 4. Check the CRT socket is tight with no bent pins on the neck. 5. Download the set-up parameters and replace the CRT/video board. | 6 |
| Blotches of colour | 1. Degauss with an external coil. 2. Adjust beam landing (Monitors control panel, Geometry, Beam Landing): top/bottom first, then check rotation, then corners. Changes save when OK is clicked. 3. Move the display away from speakers and metal. 4. Degauss again. 5. Check the beam landing coils are connected. | 6-7 |
| Screen very bright (display may shut down) | 1. Adjust brightness and contrast. 2. Check the high voltage. 3. Download the set-up parameters and replace the CRT/video board. | 7 |
| USB device on the display does not work | 1. Check the USB cable to the computer. 2. Try all four ports, and the device directly on the computer. 3. Check in Apple System Profiler that the display and its devices are listed; reseat the internal USB cables. 4. Reseat the USB assembly connectors and the cables to the power board. 5. Replace the USB assembly. | 7-8 |
| Slight jitter at 1600 × 1200 | The ATI Rage 128 card in the blue and white Power Macintosh G3, not the display. | 8 |
| Limited geometry and colour controls on an Apple video card | Use the VGA-to-Macintosh adapter on the card's DB-15 port. | 8 |
| Popping sound, perhaps with a blank screen for a moment | Normal arcing inside the CRT, most likely in the first hours or days after installation or transport, and more likely at altitude. Switch the display off and on; if needed, unplug power and cables, count to ten and reconnect. | 8-9 |
| Faint shadows or ghosting on text | 1. Check the video cable and adapter and look for bent pins. 2. Remove any extender or switch box. 3. If wiggling the cable connectors helps, replace the video cable. | 9 |
| Apple Displays Software not working | 1. Reinstall it and restart. 2. Check the USB connection by changing resolution from the Control Strip. | 9 |
| Thin horizontal lines | The two damper wires that steady the aperture grille; normal on Trinitron-type displays over 15 inches and cannot be removed. | 9 |
| Geometry button missing; USB card not recognised; error messages from the USB DSU or Apple Monitor plug-ins | Mostly set-up order with a Keyspan USB card in a PCI Power Macintosh, or a CRT/video board fitted without its set-up parameters or of the wrong version. Apple's charts give the steps for each message. | 10-15 |
CRT/video board versions
[edit | edit source]If the USB DSU reports an error after a new CRT/video board has been fitted and Write File clicked, the replacement may be the wrong version. Version 1 is 661-2116 and version 2, from November 1999, is 661-2231; serial numbers from WR9451T8HOE on have version 2. Refit the original board until a matching replacement arrives, so that the parameters can still be downloaded.[1]
Related pages
[edit | edit source]- Apple Studio Display 21
- Apple Studio Display 21 General Maintenance
- Studio Display (21" CRT, 19.8" viewable image size) Service Source
- Apple Studio Display 17 Troubleshooting Guide
- CRT Discharge Procedure
References
[edit | edit source]- ↑ 1.0 1.1 1.2 1.3 1.4 1.5 Apple Computer, Studio Display (21" CRT, 19.8" VIS) with ColorSync technology (Service Source), hosted as File:Studio display 21.pdf (see Studio Display (21" CRT, 19.8" viewable image size) Service Source). PDF page numbers: First Checklist pp. 32-33; Symptom Charts: No Video pp. 34-35, Geometry p. 35, Screen Color pp. 36-37, Screen Brightness p. 37, USB pp. 37-38, Miscellaneous pp. 38-45; Checking High Voltage pp. 46-47; Two Versions of the CRT/Video Board p. 48; Adjustments pp. 156-199.