LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Mini >> 2012 >> Cooper Base, 2D Convertible, Automatic Trans >> Repair and Diagnosis >> External Pages >> Different car >> Section 4446 (Functional Description - F10 - Engine Performance) >> Engine Performance - Functional Description >> Exhaust emission system >> Oxygen sensor
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Oxygen sensor

WARNING: This page does not describe the selected car, but rather 45 other vehicles, including the 2016 BMW M5, 2016 BMW 550i xDrive, 2016 BMW 550i, 2016 BMW 535i xDrive, and 2016 BMW 535i. However, it is still accessible from the selected car via links, so may be relevant.

The oxygen sensor consists of a ceramic coating made of zirconium dioxide (laminated). The heating element inserted in the laminate rapidly ensures the required operating temperature of at least 750 °C. The oxygen sensor contains 2 cells, a measuring cell and a reference cell. The two cells are coated with electrode made of platinum.

Fig 1: Oxygen Sensor - Circuit Diagram
G09908436Courtesy of BMW OF NORTH AMERICA, INC.
Index Explanation
1 Exhaust gas
2 Measuring cell
3 Electrode for heating
4 Electrode of the measuring cell
5 Heating element
6 Gap with ambient air
7 Ceramic surface
8 Reference cell
9 Electrode of the reference cell
10 Electrode of the measuring cell
11 Electrode of the measuring cell
12 Measuring gap

The oxygen sensor provides seamless, continuously-variable response while monitoring fuel ratios ranging from 0.65 to 2.5 (continuous characteristic curve). This oxygen sensor works with a lower heater output than a conventional oxygen sensor. In addition, this oxygen sensor is ready for operation more quickly. Current is applied at the measuring cell. This pumps oxygen into the reference cell in a process that continues until a voltage of 450 millivolts is present between the reference cell's electrodes. The applied current at the measuring cell is the measured variable for the fuel-air ratio. This enables the oxygen sensor emissions control to set any desired air/fuel ratio in the combustion chamber.