Battery dead - in settings it will not let me select comfort settings and i think it might be something int there draining the battery

So what does your mechanic think is wrong ? Battery dies overnight while sitting or when driving the battery goes dead ? Two different problems . Going dead overnight means there is a parasitic drain on the battery . ( something is staying on ) Going dead while driving means the alternator isn't charging the battery .

When does it go dead ? Over night , while driving ? Two different diagnostic's ! If it goes dead while driving the alternator is not charging the battery . If it goes dead over night there is a parasitic drain on the battery , something is on , using current . You don't say what make , model and year vehicle but most all vehicles from the mid 80's on have a number of control modules (computers ) . They power down after a set amount of time , an sometimes they don't power down . There are videos on youtube showing how to find a key off power drain .

The problem is that an electrical component in the BMW that should be dormant when the vehicle is shut down is actively drawing power.
The only way to track it down is to have tests run to see which circuit is drawing excessive power because there are numerous components that might be the cause.

You can learn more here...........
Solving Automotive Electrical Problems

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Hello Jr, The fact that the battery goes dead even with a kill switch would lead me to think the new battery is defective.

Do a parasitic battery drain test to find what's draining the battery

http://ricksfreeautorepairadvice.com/battery-dead-morning/

You either have a bad battery or something is draining it. A good way to test for this is to remove the pos battery cable from the battery. touch the cable to the battery post to complete the connection. If you hear something pop on, hum, buzz or click, it is staying on draining the battery. Your local auto zone, or advance auto ect will test your battery for free

if you take lead off battery touch to positive pole with everthing switced off should not get a spark as they touch .if you do then something drawing power have to find it could be an old system in car like phone or alarm causing it

If you mean it is going dead while sitting you might have a short or another issue drawing power from the battery. take your truck to your local battery warehouse/store the should have a meter thet will tell you if something is drawing on your system. It could be something simple, like maybe the mercury switch on your under hood light is bad and the light is not turning off thus running your battery dead over night.

Try going to Autozone or local auto parts store they will check your charging system for free a good battery should not go dead just sitting there ,must be something draining it a light in the trunk or glove box or a radio that doesn't go off or a dome lamp

Did AAA jump your battery? if not hook a comercial battery charger up to; or, remove recharge; your battery: this should release the locks then: you have either short draining your battery or, a bad alternator or, battery