Three problems related to brake sensor have been reported for the 2008 Ford Fusion. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2008 Ford Fusion based on all problems reported for the 2008 Fusion.
I was going down the highway when a road switches from 2 into 1 exit lane & 1 lane. The 1 continuing road has a small quick curve to it and the cars ahead of me were braking so I preemptively eased into a hard brake while taking that small quick curve and (I believe) the abs attempted or succeeded in kicking in, but as soon as that happened the brake pedal went from being stiff and braking quickly to soft and braking dramatically slower. Luckily I leave enough room even if I am going quickly and I was able to push the pedal to the floor and slow down in time. Even when pushing the pedal to the floor after the incident it still doesn't have anywhere near the braking force that it had at even 1/3 of the pedal distance as it did before. I unplugged the abs/tcs/heated seats/rear backup sensor fuse and the brake pedal surged back to normal operation. When I turned off the car, inserted the same fuse back in, and then started the car again the pedal still operates as normal working condition. This is quite a scary defect as it is the brakes failing/degrading because of an abs computer flaw that causes the brakes to fail only under the extreme circumstances in which they need to be performing 100%. Extremely dangerous flaw that no doubt has caused countless accidents because of a manufacturer flaw.
As I was driving my brake pedal suddenly became mushy. The pedal felt like it would hit the floor. I was able to stop but almost ran into the back of another vehicle. After doing some research online I found that multiple people were having the same problem and that it was the abs sensor that was going bad. Rather than spend $1,000 I simply removed the fuse to the abs module. When I did this my pedal pressure returned to normal. I took the vehicle to the Ford dealership, and they told me there was nothing they could do about it because removing the fuse cleared the codes. The mechanic returned the fuse to the proper position and the pressure is normal right now. However I am afraid that the situation will return.
After purchasing our Fusion, the brake pedal seemed very soft. We put new brakes on it but this did not remedy the problem. When driving the pedal goes almost to the floor and sudden stops are not an option! we were told by a serviceman it was most likely the "sensor or brain" of the braking system and that this was a common problem with this make of cars.