Deep Dive

Check

Result

Action

Code

 

 

 

 

 

1.

Verify if boot chime is present

Yes

Go to step 2.

 

 

when system is powered

 

 

 

 

ON. Make sure audio output

 

 

 

 

No

Reset PRAM and retest.

 

 

preferences are not set to mute

 

 

 

 

 

 

and volume is set to mid-range.

 

 

 

 

 

 

 

 

2.

Make sure no cables are

Yes

Go to step 3.

 

 

connected to external sound

 

 

 

 

No

If “Headphones” is the only

 

 

input/output ports. Go to

 

 

 

available sound output

 

 

System Preferences > Sound >

 

L11

 

 

device, replace audio cable.

 

Output and verify that “Internal

 

 

 

 

 

 

speakers” is an available option.

 

If “Digital output” is the

 

 

 

 

 

 

 

 

only available sound output

 

 

 

 

device, reseat audio cable to

 

 

 

 

logic board. If issue persists,

L11

 

 

 

replace audio cable.

 

 

 

 

 

 

 

If issue persists, replace logic

M09

 

 

 

board.

 

 

 

 

 

 

3.

Go to System Preferences >

Yes

LEFT speaker and amplifier

 

 

Sound > Output. Set speaker

 

circuitry OK. Go to step 4.

 

 

balance 100% to LEFT speaker

 

 

 

 

and play a known-good sound

 

 

 

 

No

No audio in LEFT speaker.

 

 

file. Verify if sound is generated

 

 

by LEFT speaker and that sound

 

Go to step 7.

 

 

quality is acceptable.

 

 

 

 

 

 

 

 

4.

Set speaker balance 100%

Yes

RIGHT speaker and amplifier

 

 

to RIGHT speaker and play a

 

circuitry OK. Set Balance slider

 

 

known-good sound file. Verify

 

to middle. Go to step 5.

 

 

if sound is generated by RIGHT

 

 

 

 

 

 

 

 

speaker and that sound quality

No

No audio in RIGHT speaker.

 

 

is acceptable.

 

Go to step 7.

 

 

 

 

 

 

5.

Verify if user-reported audio

Yes

Issue no longer present.

 

 

issue has been resolved.

 

Return system to user.

 

 

 

 

 

 

 

 

No

Go to step 6.

 

 

 

 

 

 

6.

Boot system from Install

Yes

Go to step 7.

 

 

DVD or another known-good

 

 

 

 

No

Known-good boot volume

 

 

bootable volume. Verify if issue

 

 

 

works OK. Troubleshoot for

 

 

still occurs.

 

 

 

 

software issue. Isolate if issue

 

 

 

 

 

 

 

 

is application-specific or a

 

 

 

 

possible OS conflict.

 

 

 

 

 

 

2010-09-09

iMac (27-inch, Mid 2010) Symptom Charts — Input/Output Devices  99

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Image 99
Apple MD094LL/A manual Device, replace audio cable, Output and verify that Internal, Board Go to System Preferences