| Problem | Possible Causes | Remedies |
| First line of display not on the top line of the screen | Alignment problem | Use the V-shift control to adjust the display |
| Display not covering the whole screen but is compressed in the center of the screen | Alignment problem | Use the H-shift control to adjust the display |
| Display not stable | Power supply fluctuations | Change power supply point |
| Interference from other devices, such as an electric heater, vacuum cleaner, etc. | Shut off these devices or shift the computer to a different location | |
| Display suddenly vanishes and reappears | Loose contact in VDU socket | Check and replace if necessary |
| Bad connections within the system | Call engineer | |
| No display | Bad cable | Change cable |
| Brightness maladjustment | Adjust brightness to maximum | |
| Bad monitor or system problem | Call engineer | |
| Bad or no color | Monitor maladjustment | Adjust monitor controls |
| Color signals are not proper | Call engineer |
Troubleshooting the Visual Display Unit (VDU)