Battery keeps draining.

You shoudl have replied to your previous post instead of posting a new thread so that whoever atnded to you can get notified and respond. This would keep the history of the process in one thread.

If the battery is failing, charging it would only keep alive temporarily and if left overnight, it is going to fail again. Was any high rate discharge test perormed? Most parts outlets provides free testing services. Get the alternator charging rate tested as well.

One way of testing is to disconnect the battery negative terminal and leave it off. If you are able to start the next morning, the battery could still be good and you have a parasitic drain which could be anything from a faulty component or relay that is keeping something on all the time, even when engine is not running.

You would need an ammeter to test for parasitic drain.

For those component that are not working, check the fuses. Use a test lamp or DVOM to ensure that you have battery voltage at both ends of fuses.

Did you have an issue with the siren or a message that said to service the alarm or siren before your battery problems? The siren and sunroof are both tied together with the LIN Bus from the Upper Control Module (your rear view mirror) so when the siren goes out, it takes down the sunroof as well. So your whole problem could be a faulty siren control module and could have caused the battery to drain down? The siren is located behinde the front passenger wheel well but after replacement it needs to be configured to the vehicle using Volvo's diagnostic equipement. As for the 12 volt outlets, most likely you have a burnt fuse and has nothing to do with your other issues. So replace the battery, the siren control module and take it in to Volvo or a Volvo specialist shop to configure the siren to your car. Good luck and sorry I missed this post and got to it late?

To replace it yourself wont be a problem. It is just the configuration is what you will need to have set up. The siren control module needs to be introduced to the rest of the network so it knows what is job is going to be?