I installed a new battery and about a week later the car wont start. As i'm backing out of a parking space the car stops, states el power system service required/ABS failure then shuts off. I tried to start it and all I hear is the engine trying to start. There is no clicking. I tried to start the car the following day and I hear no sound at all. I then have it towed to a mechanic shop. They tell me its the crankshaft sensor. I replace it, it starts...once. The battery also appears to have a problem holding a charge, falls below 12 volts every couple months. It has been just sitting around for a few months now. Mechanics haven't been able to fiqure anything out.