HP Pavilion DV4-2155 Maintenance And Service Manual page 100

Removal and replacement procedures
Remove the fan:
1. Position the base enclosure with the front toward you.
2. Remove the two black Phillips PM2.5×5.0 screws 1 that secure the fan to the computer.
3. Lift the fan from the base enclosure 2.
Reverse this procedure to install the fan.
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