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Discussion Starter #1 (Edited)
I recently sent out my cluster for repair to Doctor Bimmer at Pixel Repair NW and left the car unused for about two weeks. I received the repaired cluster and found that the car was completely unresponsive (e.g., no alarm, power unlocking, etc). I figured that something must have drained the battery. I reinstalled the cluster and put on my Battery Tender for about 12 hours. I came out in the morning and the car was still unresponsive (still no power locks, etc.). When I put in the key and turn to position one, all I can see is the airbag light barely illuminated. At this point, I figure that battery still doesn't have enough charge.

I've now taken out the battery to charge it in the house to eliminate the possibility of a system draining the battery while charging. What is interesting is that the Battery Tender is showing that the battery has 80% or higher charge (the green light is flashing). The red light is solid, which means it is charging.

I'm a bit stumped as to what I should be checking for next. Thoughts?

The only oddity that I noticed is when I disconnected the highlight switch, all the low power dashboard lights that illuminate the buttons, etc and stayed on. When I plugged it back in, the lights turned off. I left the highlight switch plugged in while the cluster was being repaired. Nothing else was modified on the car since the cluster removal.

Thanks.
 

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Interesting. When I removed my cluster I plugged back in the light control switch and the tire pressure switch. Not sure if that helped or not but I used it for a whole week and no problem with power.
 

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The battery was probably drained too far and will not recover. If you get the same result after charging in your home I would just get it replaced under warranty. It is a free replacement when it is this new.
 

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^ Yep - doesn't hurt to try a new battery since it can be replaced under warranty.
 

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Discussion Starter #6
Thanks for all the feedback. After a little bit of runaround on the phone, I managed to get in touch with the local Interstate distribution warehouse for my area. They were very helpful, great service. I brought the battery to them and it failed the load test. They gave me a new battery and receipt and I was on my way. The new battery works great and the cluster repair looks good as well.
 

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So problem solved?
 

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Discussion Starter #8 (Edited)
Yes, all set. The drained/defect battery was only outputting half (6V) of what it was suppose to (12V). Interstate replaced it immediately once it failed the load test. I was fortunate the local warehouse had two in stock.
 

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Discussion Starter #9
FWIW, I'm still a little surprised that the battery drained so much in a little over two weeks without use. Not sure if anything was related the removal of the cluster.
 

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Am I the only one not surprised? With the cluster removed, it's likely that you car never went to sleep. Without running it for two weeks, I would fully expect that your battery would be flat dead. Even a fresh battery isn't likely to recover from that. I have a stack of them over here that died before their time.
 

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Discussion Starter #12
With the cluster removed, it's likely that you car never went to sleep.
That's what I'm curious about. I do not recall seeing anything in the cluster removal instructions about using a trickle charger or plugging any of the disconnected switches. I'm hoping that I can spare someone else a rather unpleasant surprise if they need their cluster repaired.
 

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Guys, I'm hoping to do this over the next few weeks.

Can we establish a good procedure? Mine is sat on a CTEK in the garage, do I disconnect charger, remove cluster, and reconnect charger, in that order?
 

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Most battery chargers won't actually turn on and start charging till they see a load, if you connect a totally dead battery they won't start charging. I've had to connect a good battery to the totally dead one with jumper cables, then connect the charger and charge for an hour or so to get the voltage up a bit. I purchased a solar charger that will hopefully keep my car alive longer.
 
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