2001 ML320

2 months ago I was driving down a straight road doing 45 mph when all of a sudden the front breaks locked up by them selves. I took it to the local mechanic that say it was probably the break light switch as the cruise control stopped working as well.

I had them replace the break light switch and all 4 breaks as they were almost due anyway. Everything seemed fine for 2 months when all of a sudden the breaks locked up again doing about 30 mpg on a straight road. When trying to drive the breaks would lock up again as soon as I passed the 1000 rpm mark. I had the car towed and the mechanic got 2 codes:

C1120 B24/15 (Rotary speed and lateral acceleration sensor): Signal cable has Open circuit or Short circuit. (FAULT INDICATOR LAMP ON)
C1120 B24/15 (Rotary speed and lateral acceleration sensor): Signal cable has Open circuit or Short circuit. (STORED)

They checked all the wires and there were no shorts. They then went ahead and replaced the Lateral Accelerometer 163-542-06-18. I picked up the car drove about 20 miles before the breaks locked up again and the BAS light came on. I was able to get into a parking lot by keeping the car below 1000 rpm. After turning the car off for a few minutes I was able to drive another 5 miles home without the breaks engaging on their own.

The codes that show are the same as before. What else could cause this? A yaw sensor?