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| Troubleshooting |
| Symptom Charts/Miscellaneous - 40 |
Unit unable to enter | 1 | Verify using system 7.5.2 or later. | |
sleep mode | 2 | Make sure display actuator is installed | |
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| 3 | on CPU stiffener. |
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| 4 | Replace sleep switch. |
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| 5 | Replace logic board. |
Note: When replacing the logic board, check that the serial port EMI clip is attached to the bottom of the CPU stiffener. If it is missing, replace the stiffener. On international units, also replace the stiffener if the modem EMI clip is missing. The “CPU Stiffener” topic in Take Apart helps you locate and identify the two EMI clips.
Note: Perform the battery contact alignment procedure when you replace a logic board. (See Additional Procedures, “Align Battery Contacts.”)