HP Pavilion DV4-2155 Maintenance And Service Manual page 80

Removal and replacement procedures
Remove the touchpad button board and bracket:
1. Turn the top cover upside down with the front toward you.
2. Disconnect the touchpad cable 1 from the top cover.
3. Remove four Phillips PM2.5×3.0 screws 2.
4. Remove one Phillips PM2.5×4.0 screw 3.
5. Lift up 4 and remove the touchpad button board and bracket.
Reverse this procedure to install the touchpad button board and bracket.
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