Battery Cable problems of the 2011 Dodge Caravan

I have had an on going issue with my cars battery being dead after being turned off. This only happened at night. My daughter came home late and told me that the car had something ruining in the car. I also hear it and tried to start my car and again the battery was dead. I again charged it and was able to start the car as I turned it off again I could hear what sounded like a motor running even when the ignition switch was off and key removed. To prevent my battery from running down I removed the positive side battery cable to save it from being run down again. I called the dealership on 11-25-15 and told them what was going on. They told me to bring the car in on 11-27-15 and they would check it out. I meet with a service agent by the name of joey at the dealership who said he would call later. After, eight hours I called joey to find out if they were able to find anything. I was told it was the tipm and it would be costly to repair. I told him I need the car back and would call the customer service line about getting this cost covered since my car is only 4 years old. He told me that I would have to pay the $128 diagnostic fee regardless. He said that they sill wanted to check car and call Saturday. I called he was not there , was told I could pick up car and fee was waived. I was never told by anyone at the dealership that there was an ongoing issue with this part and that driving the car could result is loss of power and braking. I was surprised that they waived the fee now I understand why. I had to find out about the issue and litigation by searching the internet. I will have to replace the battery again, the alternator and tipm which will run over $1500 which we can not afford. I hope the dealership is written up for failure to warn about a possible deadly problem . Given the problem the company should pay all cost to get my car fixed.