I would like to know also. I was headed down the freeway feeling cool doing about 80 in the 04 C5 when all of the sudden it felt like I had lost control I jerked sideways I think one of my wheels locked up, it felt like an eternity but was actually only about a second. I got her straightened out. But the helpless feeling is still sticking in my gut. Immediately after the insodent the service active handling message appeared on the read out, no problems the rest of the trip. The message went away when I turned off the key and didn’t return

 

Welcome to the forum. Might check for bad grounds.