 Apple Technician Guide MacBook Pro (15-inch, Mid ... - tim.id.au

2010-08-05
Noise / Unstable Flickering
Unlikely cause: battery
Quick Check
Symptom Quick Check
Noise / Unstable Flickering
• Image flicker
• Audible noise
Deep Dive
1. Verify known-good source sound file not causing
speaker distortion.
Check Result Action Code
1. Verify if user’s issue is due to
video flickering coming from
display.
2. Verify display listed in the
System Profiler’s Graphics/
Displays device tree is not
disappearing intermittently
(refresh System Profiler to
observe).
3. Inspect and reseat the LVDS
cable connection between
clamshell and logic board.
Also test if brightness setting is
a contributing factor. Verify if
flickering has stopped.
4. Substitute a known good
display assembly to test
internal logic board video
output. Verify if flickering issue
has disappeared.
5. Verify if source of the noise
is the electrical as opposed
to mechanical. Audio noise
should not be a concern now
that LCD components are all
solid state devices including
LED backlights.
Yes Suspected flickering issue, go
to step 2.
No Audible noise issue, go to
step 5.
Yes Power and LCD panel ID are
OK. Go to step 3.
No Go to No Video symptom
code flow.
Yes Loose LVDS cable connection.
Issue resolved.
No Go to step 4.
Yes Replace clamshell assembly. L06
No Replace logic board. M04
Yes Noises that are not audible
from the normal user position
are considered acceptable.
Return unit to the user.
No Noise from another source.
Go to Noise/Hum/vibration
Symptom table.
MacBook Pro (15-inch, Mid 2010) Symptom Charts — Display 73