A few days ago we had our oil changed/along with an air filter change at local place.
Started up the van (cold weather), and noticed the “Check Engine” light, along with the VSC and Trac off lights on the control panel.
Did some research, stopped @ local Autozone, and the OBD-II code that showed up was P2241:
Definition: Oxygen sensor or A/F sensor pumping current low bank 2 sensor 1.
Probable cause:
1 - Open or short circuit condition
2 - Poor electrical connection
3 - Failed AF sensor
Should I take the van back to the oil change place…or to my Toyota dealer?
I know, I should’ve had the oil changed @ my dealership…my wife took the van in to the oil change place 
2nd question:
If I take this into my dealer, can I show them this TSB (EG001-05) and will it apply to our problem?
http://sie…202241.pdf
Kind Regards,
Chris Cassidy
916 Main Street
Jasper, IN 47546
Followup…
Found 2 more very helpful links on how to locate this low bank 2, sensor 1 for the Toyota Sienna.
http://www.toyotafans.net/p2241-bank-2-sensor-1-2004-sienna-t22774.htm
Followed the directions in the first link, and cross-referenced the picture in the second link and was able to locate this sensor.
Upon first notice, this sensor is directly below the Oil Filter.
Also, I noticed quite a bit of oil drippage on the cable and the sensor itself…
Most likely this happened when they recently replaced the oil filter.
I got down under the vehicle and cleaned off the sensor and cabling. Also, I noticed the cabling was loose, so I adjusted it some.
Got back into the van, turned on the ignition…and the “Check Engine”, VSC, Trac off lights disappeared.
So, for now, our problems have been resolved…but now I got to wondering…
If I take my van into Toyota dealer, the P2241 code will no longer be displayed.
Would it still be possible to reference the TSB (EG001-05) to have these parts replaced, as the vehicle has < 80K miles??? Or would a code P2241 be required in order to use this TSB?
Kind Regards,
Chris Cassidy