Testing the limits of the subject title, but here we go. Seems I've been needy lately here, but it happens.

Story. Monday I needed to take it to pick up a free set of BMW wheels. (I'm a BMW nut in the real world) Dead battery. I mean dead dead. Been having intermittent problems so not a total surprise. Charge,etc, drove it and 10 miles later the CEL comes on. Next day I break out the reader and it's P0037 which is O2 sensor heater. In spite of old and new ohming out the same, put the new one in and after a CEL reset the light stayed off on a brief test drive. Cool. That's a win. But, on my 15 year old OBDII reader the yellow light is on, suggesting a problem, I assume with monitors as nothing is even pending code wise.

Real question. How long/what do I have to do before it will be ready for smog. Keeping in mind again the dead battery, not just the code. '03 QX4

Before reset, freeze frame is as follows,

Stored:
P0037 HO2S Heater Control Circuit Low (Bank 1, Sensor 2)


MIL ON
MisFire Monitor Complete
Fuel System Monitor Complete
Comprehensive Component Monitor Complete
Catalyst Monitor Complete
Heated Catalyst Monitor Not Supported
Evaporative System Monitor Complete
Secondary Air System Monitor Not Supported
A/C System Refrigerant Monitor Not Supported
Oxygen Sensor Monitor Complete
Oxygen Sensor Heater Monitor Complete
EGR System Monitor Not Supported

DTC For Which Freeze Frame Was Stored P0037
Fuel System 1 Status Closed Loop
Fuel System 2 Status Closed Loop
Calculated LOAD Value 72.16 %
Engine Coolant Temperature 186.8 °F
Short Term Fuel Trim - Bank 1 -3.91 %
Long Term Fuel Trim - Bank 1 -0.78 %
Short Term Fuel Trim - Bank 2 -10.16 %
Long Term Fuel Trim - Bank 2 -2.34 %
Engine RPM 2762.50 rpm
Vehicle Speed Sensor 72.5 mph

https://www.nicoclub.com/service-manual ... 3%2Fec.pdf
If you look at the information starting on EC-87 (which is admittedly Greek), the SRT for P0037 should just take a couple of full warmups at idle and then trips on the highway with the cats lit. The trouble here is that your battery issue may have wiped all your SRT's. You need to check them again and see which monitors are showing Incomplete. If the cat monitor was lost then you'll need the whole nine yards for driving patterns before they'll all clear.

I was hoping you'd chime in and afraid you'd have something like that to say. Oh well, better to have an idea than go in and fail.

Unlike the immortal Mendy Rudolph, when I don't see 'em, I don't make 'em up. Sorry it was bad news.

But a good report. Yesterday it was flashing icons and a yellow light on my codereader. Looking and printing the driving pattern on page 92, armed with a stopwatch and cruise control I attempted to duplicate it. Got back after an hours drive, plugged in the reader and green light and no flashing icons. Hopefully that means what I think it means. So apparently it is possible to follow the driving pattern and reset things. Maybe. We'll see.

Thanks again!

Depends on your scanner, but yes, I'd say that's a good sign!