My wife just had the check engine, VSC, and Traction Off lights come on. I have checked this forum and then tightened the gas cap and topped off the brake fluid. We had a similar situation last summer while we were on vacation. The condition lasted a couple of days then and then stopped by itself, so I never took it to Toyota. I guess now I'll have to take it in while it's still under warranty. Any ideas about these lights/sensors?
I did go out and top off the brake fluid and retighten the gas cap. The gas cap was loose. I have heard that after it is retightened the car needs to be driven several times in order for the sensor to reset. I drove it and I think there is a slight miss. This engine is so smooth and quiet, but I could feel a slight vibration in my knee through the door panel,and a very slight one thru the steering wheel. The tach seems to move a little at idle,but very little, almost imperceptable. I plan on taking it to Toyota tomorrow. Hopefully the lights are still on and they can find a code.
Service rep just called. They are changing the coolant and the thermostat, plus a sensor (sorry, I forgot what sensor). He said they coolant and th thermostat were not up to snuff, so they couldn't be read correctly. I'm not sure if it was a coolant sensor or an air/fuel sensor. I know the rep said the sensor was deep down in the engine. I'll follow up with another post regarding exactly what sensor(s) were changed when I get the car back, if anyone is interested.
The codes were P2241 air/fuel sensor malfunction, sensor bank 2, sensor 1
and
P0128 coolant temp.
Toyota replaced both sensors as well as the coolant and thermostat under warranty.
Does anyone know if these sensors are covered under the 3yr/36,000 mi. warranty,or under the 4yr powertrain warranty, or under the emission controls warranty,which I think is 8 yrs.? The service rep. was alluding to the the basic three yr. warranty,but it seems tome that these sensors are part of the emission controls and sould be covered under the manadated 8yr federal emissions warranty. Does anyone know for sure? T.I.A.
I realize I'm replying to a pretty old post, but I did find the exact answer to this question and I thought it might be helpful to others (since I'm running into this exact same issue with my O2 sensor). According to the Toyota TSB dated Feb 2, 2005 (MIL ON, DTC P0031/P0051/P2238 AND/OR P2241)...
Quote:
Under certain driving conditions, some 2004 model year Sienna vehicles may exhibit a M.I.L. "ON" with at least one of the following DTCs:
* P0031 (Oxygen Sensor Heater Control Circuit Low [Bank 1, Sensor 1])
* P0051 (Oxygen Sensor Heater Control Circuit Low [Bank 2, Sensor 1])
* P2238 (Oxygen Sensor Pumping Current Circuit Low (for A/F Sensor) [Bank 1, Sensor 1])
* P2241 (Oxygen Sensor Pumping Current Circuit Low (for A/F Sensor) [Bank 2, Sensor 1])
Applicable Warranty*: This repair is covered under the Toyota Federal Emissions Warranty. This warranty is in effect for 96 months or 80,000 miles, whichever occurs first, from the vehicle's in-service date.
* Warranty application is limited to correction of a problem based upon a customer's specific complaint.
Last edited by jstefanski; 02-14-2009 at 07:26 PM.