I have a Corolla Sport 2013. I don't know what the "Trac" feature is. I never shut it off. I notice when I hit a patch of ice and brake, I slide right thru the ice and hear a grinding noise on brakes.
New"ish car brakes grinding when I hit them while approaching ice patch. Think i smell something burning, but not sure.
trac is traction control helps with braking and sliding the grinding noise is the ABS which is the anti-lock brake so your brakes will not lock up on you in a patch of ice so they work together
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