Panasonic SA-BTT775GA Service Manual page 88

Step 2 Release Red Wire and Black Wire from the slots.
Step 3 Release the 5P FFC from the slot of BD Mechanism
Unit (BRS1P).
Step 4 Release the catch.
Step 5 Lift up and remove Loading P.C.B..
10.15.8.2. Assembly of Loading P.C.B.
Step 1 Insert the FFC through the slot of BD Mechanism Unit
(BRS1P).
Step 2 Insert the Loading P.C.B. into the slots.
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