1. Check the brake fluid level. If the brake fluid is low, it can cause the ABS system to malfunction and the water warning light to come on. The brake fluid reservoir is located under the hood, near the brake master cylinder. The fluid level should be between the "MIN" and "MAX" marks on the reservoir.
2. Check the wheel speed sensors. The wheel speed sensors are responsible for detecting the speed of each wheel. If one or more of the wheel speed sensors is faulty, it can cause the ABS system to malfunction and the water warning light to come on. The wheel speed sensors are located at each wheel, near the brake caliper.
3. Check the ABS control module. The ABS control module is the brain of the ABS system. If the ABS control module is faulty, it can cause the ABS system to malfunction and the water warning light to come on. The ABS control module is located under the hood, near the brake master cylinder.
If you are not comfortable checking these things yourself, you should take your car to a qualified mechanic.
If you find that the brake fluid level is low, it is important to fill it up as soon as possible. Driving with low brake fluid is dangerous, as it can cause the brakes to fail.
If you find that one or more of the wheel speed sensors is faulty, you will need to replace the sensor(s). Replacing a wheel speed sensor is a relatively simple job that can be done in about an hour.
If you find that the ABS control module is faulty, you will need to replace the module. Replacing an ABS control module is a more complex job that should be done by a qualified mechanic.
