x_lead < 5 or (x_lead < 17.5 and self.v_rel < 0.5)

selfdrive/controls/lib/planner.py

@@ -235,7 +235,7 @@ def update(self, CS, lead, v_cruise_setpoint):
 
     # Defining some variables to make the logic more human readable for auto distance override below
     # Is the car tailgating the lead car?
-    if x_lead < 15 and self.v_rel >= -1 and self.v_rel < 1:
+    if x_lead < 5 or (x_lead < 17.5 and self.v_rel < 0.5):
       self.tailgating = 1
     else:
       self.tailgating = 0