Hello Jamie, As martin has said, It is fairly easy to test wheel sensors from this position. The sensor resistance is 800-1400 ohms. There is also a soloniod on the hydtaulic modulator N/S on fire wall which from memory sits horizontal to vehicle, screw in cylinder type unit with an hex head at base end and a 2 wire plug at the top, When this plays up it makes the brake pedal feel as if it has non assisted brakes(makes you wake up when this happens as you go for a test drive thinking "nothing wrong with these brakes whats the customer on about!!".