Also, DO NOT CONTINUE TO CLEAR THE TESTER OR DISCONNECT THE BATTERY. A reset puts you right back where you were and you have to start the whole process from the beginning. Those 'drive cycle' internal tests are many times a PITA for lots of people. I have neighbors who ask me, and I tell them sometimes you have to drive 250 miles over a period of 3 weeks before the magical inclusion of all the test variables are counted. 180 is right, the 'drive cycle' is various speeds with other rqmts thrown in. You have to find the drive cycle requirements listing (dunno where that is), and follow it to the letter. Sometimes following it still doesn't reset that one monitor and people tell me it finally went off a couple of weeks later by itself. If you get frustrated/confused/or allow someone to use a OBD2 tool to reset (or any other resetting device) you'll have to start all over again for ALL the internal calibration/test monitor cycles. Disconnecting the battery also resets these parameters in some cars, I just know people keep resetting the codes or disconnect the battery in haste, winding up right back where they started again with that last drive cycle test holding the 'yellow' light on. Those monitors are a self test of the hardware and they just make problems for a lot of people who spend huge amounts of $ on stuff they do not have to. Other than this 'wait and see after you find and run that specific drive cycle' there is just nothing else I can suggest. DO NOT CONTINUE RESETTING THE SYSTEM OR DISC BATTERY.