'10 Q7 TDI in for diesel smog check. O2 sensor heater not ready error. No CEL. All other sensors are ready. Tech says can't move forward till we clear the error. I've tried cold-start, idle 2 1/2 mins, accelerate to 50, slow to 20, accelerate to 50. stop. Did that for a few days, same error.
Trying to avoid going to dealer if it's just a proper drive cycle to clear it up.