I started getting an intermittent AFS flashing light and warning. Now it's constant. I got a great deal on a brand new front sensor on Amazon and put it in. No change. Now looking into getting a rear. Neither of them looked rusty or corroded.Does any one know if a code reader might identify my issue before dropping 265 on a rear sensor?

 

My LS430 had both sensors rusted out. I replaced the rear and AFS kept flashing.

Once I also replaced the front, it stopped.