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Question Reply

Customer Question:

When they scanned my car, the error code said it was “Bank ‘X’, Sensor ‘Y’”. What does this mean?

1A Auto Replies:

In order to read and diagnose oxygen sensors correctly, the computer gives each a sensor a specific name based on its bank and sensor numbers.  Bank refers to the side of the vehicle that the oxygen sensor is on.  Bank 1 refers to the side of the motor on which cylinder 1 is located.  If the engine is a four cylinder, there will only be one bank.  If the vehicle is a six-cylinder or larger, Bank 2 would be the located on the opposite side of the vehicle from Bank 1 (ex. Bank 1 would be on the driver side while Bank 2 would be on the passenger side).  The sensor number refers to the order in which the sensor is located from front to back of the vehicle.  The sensor closest to the front of the vehicle would be Sensor 1.

1A Auto Parts is a Circle of Excellence Fifth Time Award Winner!

About 1A Auto

Welcome to 1A Auto! We are a family owned business, and for the last 50 years, we have been using the same high quality aftermarket replacement auto parts that we now offer for sale online.

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