Infotainment Unit Draining Battery

[George Ab]

Documenting this in case anyone has a mysterious intermittent dead battery and are unable to find cause. My battery would be completely drained and it was an intermittent problem. Battery would go days without a problem and then suddenly dead. After ruling out the obvious of a bad battery, performed all the normal failure analysis for trickle drain (looking for micro voltage across fuses) etc. which was unsuccessful. After many months of disconnecting battery at night, I was doing something in my car and the infotainment unit turned on by itself. I then put a switch in-line with infotainment fuse for a few weeks which verified the problem was the head unit. Replaced head unit, removed CP (component protection) Functional enablement codes (FeC’s) and problem solved. The problem unit was an early MIB2 3Q0035844 which I swapped with a 3Q0035844B. Jack Kirry removed component protection and reinstalled the FeC’s. https://www.golfmk7.com/forums/inde...o-mib2-infotainment-conversion-part-1.343701/

 

[Golfs everyday]

GJ on the find! Sounds like it was a huge headache.

 

[Saidoz98]

@George Ab
Hello!! I’m having the same problem here and the las work I’ve done was upgrading to MIB2 so I’m suspecting that the new unit has something to do with this drain so can you help me with diagnosing this, today I have removed the infotainment fuse F12 SC12 and both the head unit and the screen are now always off and I’m measuring battery voltage every day and I will not use the car for a week so what should my readings of battery voltage be. Another thing that I’ve noticed that the new unit temperature goes really high that it can burn your hands if you held it too long and I don’t know if this is ok or not or this is an indication that the unit draws higher current than usual.

Thanks in advance.