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Toyota Repair/Check engine light, VSC, Trac Off


QUESTION: Turned on lights, disconnected positive battery cable, waited 30 minutes reconnected.  Lights briefly went out, then came back on.  Same thing happened when I disconnected the negative battery cable.

Car runs fine.  A local shop ran codes and saw the following:


Any idea what the problem is?  Any idea how to fix?

Thanks, Dan

ANSWER: Hello, I need to know the rear model and mileage of the vehicle, thanks.

---------- FOLLOW-UP ----------

QUESTION: Vehicle is a 2010 Toyota Sienna LE (manufactured in 2009), mileage is 65,149, V6.

Thanks, the first concern are the P0051 and the P2197, both codes are for the air/fuel ratio sensor bank 2 sensor one, this is located in the exhaust manifold near the radiator, a common problem, you can see the sensor wire coming from the manifold, you may need a special O2 sensor socket to remove it. Replace this sensor and the C1201 should then clear without any further action required, it's an abs/ skid control code which can be triggered by the check engine light by default. The last one is an immobilizer malfunction detected, if the vehicle starts normally and runs I don't see a connection between this and the other codes, maybe a non transponder key was used at some time in the past.  

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Ted Ritter


I have more than 28 years experience as toyota technician, I will be able to answer most questions related to the Toyota product line up to the present year models,I am located in the US but welcome questions from other regions of the world. When asking a question please provide specific information: year,model, engine,transmission information. Provide as much information as possible including a brief repair history if possible. I have been a volunteer here for more ten years an have answered over 16,000 questions helping Toyota owners with their problems and save thousands of dollars without any compensation, some of my answers are published on many other websites including google and various automotive forums. DONATIONS ARE VERY MUCH APPRECIATED, IF YOU HAVE RECIEVED HELPFUL INFORMATION PLEASE MAKE A DONATION. AS OF TODAY (JULY 22, 2014) ALL REQUESTED GRAPHICS, ILLUSTRATIONS, DIAGRAMS, PHOTOS, WILL REQUIRE THE MINUMUM DONATION UP FRONT.


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