2004 toyota sequoia with approx. Mileage of 15000 came in with a complaint stating that theres a grinding noise from the rear of the vehicle. After test driving, it was the differencial gears making a noise. I changed it completely(the whole assymbly) and now the abs light stays on. Ive checked the voltage from the sensor and all 4 are within spec. Reading at 1.24 ohms. Changed the abs module computer, reseted it, it still came on after test driving. Ive also done the yaw sensor reset and it still comes on. What could be the problem?