I recently replace the transaxle seal on the passenger side of my cobalt, I unplugged ABS sensor when doing the job. When I reconnected the ABS sensor I applied dielectric grease. When I started the car the ABS light turned on.

Anyone have an explanation why the ABS light is on?

 

Don't know but pull the battery for a bit and see if it resets.

 

id take the plug out again and clean both male and female plugs with electric parts cleaner. reapply the grease and see what happens.