My car is throwing a SES light with the 0420 code which is that the catlytic converter is below its threshold. I have reset the code three times and driven the car once over 220 miles on a short trip. No codes were posted during the trip and nowhere else in my town. The code keeps being posted in the same section of a road I take to work near a microwave tower. Is it possible that the tower and its emissions is setting the code off? I intend on changing the OXY sensor on the drivers bank but hesitate on spending money on a new converter. Injuneer and Shoebox...you guys always save me, help with this one????