iMac (27-inch, Mid 2010) Symptom Charts — Startup and Power 49
2010-09-09
Deep Dive
Check Result Action Code
1. Boot from Install DVD and
Verify if issue is still visible.
Yes Go to step 2.
No Issue likely caused by
software or driver issue.
Troubleshoot for software
issues. Make sure all software
and rmware updates have
been installed.
2. Verify if issue is visible on an
external display.
Yes Issue is NOT caused by
internal LCD display.
Go to step 3.
No Go to step 6.
3. Remove video card, inspect
connector for damage or
corrosion. Reinstall video card
and retest. Verify if issue still
occurs.
Yes Replace video card.
Go to step 4.
M04
No Issue resolved by reseating
video card.
4. Verify if video corruption issue
is still present.
Yes Replace logic board. If a video
card was replaced, reinstall
the user’s original video card.
Go to step 5.
M04
No Issue resolved with
replacement video card.
5. Verify if video corruption issue
is still present with replacement
logic board installed.
Yes Return to step 1 and retest.
No Issue resolved with
replacement logic board.
6. Inspect glass panel. Verify if
issue is caused by condensation
or contaminants on inside/
outside surface of glass panel,
or on surface of LCD panel.
Yes Clean glass and/or LCD using
procedures in Glass Panel
take-apart chapter.
Identify possible sources
of contamination (nearby
cigarette/cooking smoke,
heavy airborne dust, etc.)
to prevent recurrence.
Condensation should
dissipate after computer has
been running a few hours.
No Go to step 7.