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2.5 USB FDD Troubleshooting 2 Troubleshooting Procedures
Check 2 USB FDD may be faulty. Replace it with a new one. If the problem still occurs,
perform Check 3.
Check 3 Connect USB FDD to each port embedded on system board and on SJ board.
Then, check if it works properly. If it does not work properly when connected to
CN4621/CN4620, perform Check 4. If it does not work properly when connected
to CN4610 or all ports, perform Check 6.
Check 4 USB harness may be faulty. Replace it with a new one following the steps in
Chapter 4, Replacement Procedures. If the problem still occurs, perform Check 5.
Check 5 SJ board may be faulty. Replace it with a new one following the steps in Chapter
4, Replacement Procedures. If the problem still occurs, perform Check 6.
Check 6 System board may be faulty. Replace it with a new one following the steps in
Chapter 4, Replacement Procedures.
2-40 [CONFIDENTIAL] QOSMIO G20 Maintenance Manual (960-511)