[comp.sys.ibm.pc.hardware] Diagnostic challenge: 2 IBM EGA monitors failed

sher@bbn.com (Lawrence D. Sher) (05/02/91)

When a monitor fails, it could be anything.  But when two monitors
partially fail in the identical way, one cannot help suspect that
this is a known failure mode, and fixing it must be known too.

So...
I have two IBM EGA "Enhanced Color Display" monitors, IBM type 5154,
that have identical failure patterns.  The symptoms:

When first turned on, the picture is OK except for 
   unusual background brightness
   occasional whole-screen glitches
   ocassional raster lines near the top or center that seem misplaced

During the first few minutes of warm-up
   the unusual background brightness fades to a normal black

A few minutes later a new mode of behavior suddenly appears:
   the background brightness level is up again
   the raster appears ragged, possibly every other line misplaced by 1-2
      pixels
   the beast shrieks (15 kHz?)
   it smells like a component has overheated

Momentary disconnect of the signal line restores normal operation for a
few minutes.

Any ideas?
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