Specifications

Troubleshooting Symptom Charts - 5
until the normal startup procedure has ended (since you
might have no raster, allow one to two minutes). If the “no
raster” condition is related to an old version of software,
then the image will become active and the Mac desktop should
appear.
3 Shut down computer and monitor. Discharge CRT. The CRT/
video board might not be properly secured to the neck of the
CRT. Check that CRT socket connection is tight.
Note: To confirm proper connection, place your open hand on
the back of the CRT/video board. With gentle pressure, try
jiggling the board. There should be no movement or sound. If
there is movement or if the CRT neck emits a grinding noise,
the CRT is most likely damaged; in that case, contact Apple
Technical Support.
4 One of the CRT socket wires may be improperly secured.
Refer to “CRT/Video Board” in the Take Apart chapter to
secure the red and white wires correctly in the CRT socket.
5 Check for presence of high voltage (see “Checking High
Voltage” in this chapter). High voltage is present if you hear
a rustling sound when the display is turned on or off.
6 Refer to “Downloading Setup Parameters” in this chapter.
• If you are able to download data, replace the main
deflection board. If the symptom persists, return the
display for whole unit or head unit replacement (following
the service strategy in your region).
• If you are not able to download data, call Apple Technical
Support. (In the US, call 1-800-919-2775, option 3.)
Geometry
Shape of raster is
distorted
1 Rotate monitor at least 90 degrees or move it to another
location. If symptom changes, there is an environmental
problem and monitor is operating normally.
2 From the Monitors & Sound control panel, click Geometry
icon and then click Factory Settings button.
3 If necessary, adjust AppleVision controls to optimize front-
of-screen performance.
4 Read “First Checklist” at the beginning of this chapter.
5 Call Apple Technical Support. (In the US, call 1-800-919-
2775, option 3.)