Apple MD094LL/A Manual Do Utilizador

iMac (27-inch, Mid 2010) Symptom Charts — Mechanical 

 2010-09-09

1.  Verify if any tape, gasket, cable 

label, or cable is touching 

the fan blades and causing a 

ticking noise.

Yes

Secure the material so it 

doesn’t touch fan blades. If 

tape adhesive has lost its 

stickiness, replace that section 

of tape.

No

Go to step 2.

2.  Run latest available Apple 

service utilities and verify if it 

reports one or more errors.

Yes

Locate affected part and 

check for correct cable 

seating. Use ASD Error 

(in General 

Troubleshooting) to decode 

error. Follow instructions in 

table for resolving error, then 

retest.

No

Go to step 3.

3.  Verify if noise sounds like one 

or more fans are spinning faster 

than expected.

Yes

Reset SMC by disconnecting 

power cord for ~15 seconds 

then retest. If issue continues 

go to step 3.

No

Go to step 6.

4.  Verify if noise changes when 

optical drive is being accessed 

or media is inserted or ejected.

Yes

Suspect issue with optical 

drive or media used.  

Go to 

symptom flow.

No

Go to step 5.

5.  Mute the system volume. Verify 

if issue still occurs.

Yes

Go to step 6.

No

Suspect issue with speakers 

or audio amplifier circuitry.  

Go to 

 symptom flow.

6.  Adjust brightness on display 

between maximum and 

minimum settings. Verify if 

issue changes depending on 

brightness level.

Yes

Suspect issue with LCD 

display or backlight controller 

board. Go to 

 symptom flow.

No

Go to step 7.