Panasonic SB-WA500PP Service Manual page 22

Step 4 : Flip back the D-Amp P.C.B..
Caution : Avoid touching the Heatsink Unit due to its high
temperature after prolonged use. Touching it may lead to
injuries.
Step 5 : Fix the Heatsink Clip onto the Heatsink unit.
Caution : Ensure the Heatsink Clip is fully inserted onto
the Heatsink unit.
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