Sony Ericsson W850 Troubleshooting Manual, Mechanical page 22

Problem Area
Items to Check
A & B keys Visually inspect whether the main flex
film is properly connected to its
connector on the navigation key foil
assy
4/000 21-1/FEA 209 544/104 A
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Company Internal Sony Ericsson Mobile Communications AB
Trouble Shooting Guide, Mechanical
Repair Action
•
If improperly connected – Re-establish
proper connection.
•
If main flex is damage – replace it.
Reference Image
22(42)