Camera switched on about to take a photo. Somehow I managed to inadvertently open the battery compartment and the batteries fell out. Camera now inoperable with lens holder in out position. Green light flashes when power "On" button pressed but camers does not respond any further

Rear Compartment Lamp
The BCM supplies battery positive voltage from the INT LAMPS fuse at all times through the inadvertent power courtesy lamps circuit to the rear compartment lamp. When the rear compartment is opened, the rear compartment lamp switch closes to ground and the lamp illuminates.

Overhead Console Lamp and Roof Rail Courtesy/Reading Lamps
The courtesy/reading lamp is a duel purpose lamp that can be illuminated two different ways. First, the lamp can be turned ON during courtesy lamp operation as described above. Second, the lamps can be turned ON individually for reading lamp operation by the lamp switch. The BCM supplies battery voltage from the INT LAMPS fuse through the inadvertent power courtesy lamps circuit to the courtesy/reading lamps for reading lamp operation only. Ground for the courtesy lamp module or the roof/rail reading lamps is provided at G402

Courtesy Lamps
When either one of the front doors is opened, ground is applied through the door latch door open switch and the door open switch signal circuit to the door module indicting the door open position. In response to this signal, the door module sends a GMLAN serial data message to the BCM of the door open position. Or, when either one of the rear doors is opened, ground is applied through the door latch door open switch and the rear door open switch signal circuit to the BCM is indicating the rear door open position. Once a door open message or signal received, the BCM will then apply battery voltage from the CTSY/RF TRN fuse through the courtesy lamp supply voltage circuits illuminating the lamps listed below:
• Overhead console lamp
• Roof rail courtesy lamps
• Footwell courtesy lamps The BCM receives battery voltage from the INT LAMPS fuse in order to supply power to the inadvertent courtesy lamps. Inadvertent power courtesy lamp feature provides a similar function for the interior lamps as a retained accessory power feature. The BCM will energize the courtesy lamps supply voltage circuit when the BCM is in the active state (awake). When the inadvertent power courtesy lamps supply voltage circuit is energized, it supplies voltage to all the interior lights listed below. The BCM will continue to supply voltage to the interior lamps after the ignition is turned OFF so that the interior lamps may be operated.
• Overhead Console Reading Lamps
• Roof Rail Reading Lamps
• Vanity Mirror Lamps
• I/P Compartment Lamp
• Rear Compartment Courtesy Lamp
In the event that any of these lamps were to remain illuminated for a period of more than 20 minutes with the ignition switch in the OFF position and no BCM input activity, the BCM will deactivate the inadvertent power supply voltage circuit to prevent a total battery discharge condition. The BCM receives battery voltage from the CTSY/RF TRN fuse in order to supply power to the courtesy lamps. The BCM applies this voltage to the courtesy lamps through the courtesy lamp supply voltage circuits. When any door is opened, the door open switch contacts close and the BCM receives a door-open signal. If the BCM receives a door lock or unlock signal, the BCM will activate the courtesy lamp supply voltage circuit, providing battery voltage to the dome lamps and the left and right footwell courtesy lamps. The courtesy lamps can be manually activated by placing the interior lamp switch in the DOME position. For more detailed information concerning courtesy lamp operation refer to Interior Lighting Systems Description and Operation.

This is both a courtesy and safety issue on many high end vehicles. The light from the interior lights can cast enough light to get to front door and possibly show dangers in your path. And after first getting into you car and starting it, you can check the back seat for any unwanted hitchhikers. As for the 10 minute timer, I don't know if this can be adjusted. A Chiltons/Haynes repair manual for you car may have that answer, or, the Buick dealership shop foreman. Best of luck.

Your camera will work with AA batteries.
Always be sure the batteries are charged.
Insert the batteries correct plus to plus and minus to minus. Only one battery the wrong way around and the camera won't work.
Check contacts of the batteries and in the battery compartment of your camera. Dirty or oxidised contacts can be cleaned with a dry cloth. Never use sharp tools to clean contacts or anything in or on your camera.
Always charge the batteries before using it for the first time, or if you have not used it for a long period. 3 months is a very long period.
Also check if the battery door is closed correct. Most cameras do have a switch connected to the battery door. If the switch does not work correct, it could be you can't switch on your camera.
Do not use alkaline batteries unless it is absolutely necessary. In most cases, alkaline batteries have a shorter service life than NiMH. Alkaline battery performance is limited, especially at low temperatures. The use of NiMH batteries is recommended.
Never use manganese (Zinc-Carbon) batteries in your camera. They can't deliver enough power and can start leaking, causing damage to your camera.

First, make sure that you downloaded any photos so that you don't lose them. Next, open the battery cover and remove the battery. Count to twenty, then put the battery back. Try switching on and off and see if that cures the problem. If not, remove the battery again and look to see whether there is a secondary lithium watch size battery in the battery compartment. If so try removing and replacing it. Then put the main battery back and try switching the camera on and off. Then remove the memory card and try switching it on and off. Then, if it still won't shut off, try going through the menus and reset the camera to factory/default settings.

Leaving the battery compartment open) shouldnt affect the camera (unless you managed to get water or mositure inside). Try new batteries first

you could try and put all the info about your camera in to google search..or the same on ebay.

The switch is a micro switch that is depressed(and not sad :)) by a plastic tag moulded on the battery cover. Once the cover is moved into position and closed, the tag presses on the micro switch closing the switch and thus removing the error message. As with any switch, a switch is simply open or closed, Open = high resistance or O/L, while closed = 0 ohms reistance. You can use a small wire to overcome the switch by soldering the wire to both tags of the switch so it is permenantly 0 ohms. This will send a message to the microprocessor that cover is closed and camera ready for use. Hope this helps.
Twitcha

Only by examining the camera your self will you find out If you managed to purchase a part- perhaps an installation diagram is available from the same source.

do you think you broke the switch when it landed mysinse wont come out on my camera so i finally took it apart you know what i found a small watch battery on the circut board maby yours got docked when it fell i wonder how many people have dead batteries and cant figure out what is wrong with their cameras