Volvo 2005 S40 Manual page 55

5. Pry out (2) and replace the battery. Avoid touching the battery and its contact surfaces with your fingers.
6. Press the cover back into place and tighten the screw.
7. Reinsert the key blade in the remote control.
NOTE: The old battery should be disposed of properly at a recycling center or at your Volvo retailer.
pg. 92 Locking and unlocking
Locking/unlocking the car from the inside
The switches near the door opening handles on the driver's and front passenger's doors can be used to lock or unlock
all doors and the trunk, and to set the alarm.
Unlocking:
Press in the upper section in the lock button. A long press (at least two seconds) also opens all the side windows.
Locking:
Press in the lower section of the lock button.
NOTE:
The doors cannot be opened by pulling up the lock button.
Each door can also be locked manually using the lock button on that particular door. This applies only if the car has
not been locked from the outside.
The doors can also be unlocked (and the door opened) by pulling the handle in the door twice.
Opening the trunk from the inside