Originally Posted by BoilerUpXFire

PLEASE READ THIS.

First off, even when a battery is testing ok, if it is more than 3-4 years old, replace it, these cars are VERY sensitive to voltage irregularities.

Second, the sensor I replaced is a WHEEL SPEED SENSOR and is in the hub assembly. It tells the car how fast each wheel is traveling and compares the data across all 4 wheels, if one sensor is dead, it can not confirm your speed and as a safety measure, it will deploy the spoiler and blink the light on the dash.