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| Troubleshooting |
| Symptom Charts/Peripherals - 27 | |
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| connected to | 1 | Verify that External Modem is selected in CDEV. |
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Device | |||||
external modem port | 2 | Verify that System is 7.5.2 or later. | |||
does not work | 3 | Check cables. | |||
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| 4 | Test device with known good computer. | |
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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.”)