One problem related to battery dead has been reported for the 2005 Kia Motor Sorento. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2005 Kia Motor Sorento based on all problems reported for the 2005 Sorento.
Over the last 4 years I have replaced the battery 3 times. Each time, the car had been sitting for a day or 2 and when I attempted to use it, the car/battery was dead. I have seen on line that the tccu (transfer case control unit) is probably the culprit and it is almost impossible to identify because the computer will show no history of it. Evidently, on rare occasions the computer will begin running diagnostics on the tccu when the car is being shut off. The drain on the system is enough to wipe out the battery. I have contacted kia - they do not acknowledge the problem and all they want to do is run a diagnostics test which will tell them nothing and will cost me more money. The cost of a new tccu is about $1500, probably why kia has no interest in replacing it.