Car may throw A/F Sensor Heater Circuit in california models due to faulty battery. If voltage drops toward 8V when the car is starting sometimes this code will get thrown (1135). The battery still tested good with a load tester.
When the battery was replaced the problem went away. This is of course after changing:
X2 on that! My battery was going and I got the same code. I was surprised how long the dying battery lasted and still started my car. Once I got a new battery no more codes and wow how fast the starter turned the car over.