Electrical problems

[SirHiss]

Hello E53 lovers!

Long time lurker, first time poster here.

I bought my 2006 3.0D Sport with 84k on it back in March 2020 and have been loving it, until 2 weeks ago when it started having some electrical problems! I wonder if anyone can help me figure out what is going on?

So, a timeline of the symptoms:

First I noticed my gauge cluster lights flickering. Turning the brightness down made it far more obvious. At the same time i also noticed the brake lights stayed on after I have left the car and locked it! Very strange! To get them to turn off took a few on/off turns of the ignition.

A few days later I noticed my indicators kinda skipping a beat, if that makes sense. Or a delay when activating them. That night the battery died overnight. I charged it back up with my ctek and all was good again (for 2 days) (I should note that I barely drive the thing these days).

A couple of days later and the indicators stopped lighting up on the dash all together, along with, as I discovered later, the high beam icon. Around this time, I also noticed that whenever I turned the ignition on, the headlights would come on regardless of where the switch was. Turning the headlight switch would return it to normal functionality. Battery then died again overnight. Charged up again, lasted a couple more days.

After a lot of forum research I took a punt at replacing the ignition switch and gave it a brand new battery. It did not fix the problem.

So we come to today. Last night I woke up at 4am to my car alarm dying and waking up the neighborhood! I tried to put my ctek on it but it would not charge it. It tripped out.

I am pretty sure there is a problem with the LCM due to all the light problems but I have no idea what is draining the battery!

Help me, obi wan