P1276 - Air Fuel Ratio Sensor 1 Bank 1 Circuit High Voltage Detected

Repair Importance Level: 3/3
Repair Difficulty Level: 3/3   
Comments  |  Add Comment

Possible causes

  • Faulty air fuel ratio (A/F) sensor 1 heater Bank 1
  • Air fuel ratio (A/F) harness is open or shorted
  • Air fuel ratio (A/F) circuit poor electrical connection

Possible symptoms

  • Engine Light ON (or Service Engine Soon Warning Light)

P1276 Description

The A/F sensor is a planar dual-cell limit current sensor. The sensor element of the A/F sensor is the combination of a Nernst concentration cell (sensor cell) with an oxygen-pump cell, which transports ions. It has a heater in the element.

The sensor is capable of precise measurement λ= 1, but also in the lean and rich range. Together with its control electronics, the sensor outputs a clear, continuous signal throughout a wide λ range (0.7 < λ < air).

The exhaust gas components diffuse through the diffusion gap at the electrode of the oxygen pump and Nernst concentration cell, where they are brought to thermodynamic balance.

An electronic circuit controls the pump current through the oxygen-pump cell so that the composition of the exhaust gas in the diffusion gap remains constant at λ = 1. Therefore, the A/F sensor is able to indicate air/fuel ratio by this pumping of current. In addition, a heater is integrated in the sensor to ensure the required operating temperature of 700 - 800 C (1,292 - 1,472 F).

OBDII Code P1276 - Air Fuel Ratio Sensor 1 Bank 1 Circuit High Voltage Detected - AutoCodes.com

P1276 Information for specific makes

Need more help?

Get the P1276 code diagnosed by a professional: Find a repair shop in your area

Related Information

P1276 Comments

Help us improve AutoCodes.com. Leave a comment below or tell us if the information above help you fix the code. What are the symptoms on your vehicle for the P1276 code? Have you replaced any parts?
Any information is appreciated. Thanks
Top ⇧