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Rear Oxygen Sensor: Inspection

Check that the rear oxygen sensor has no deformation, cracks or other damages.
Measure the resistance between rear oxygen sensor terminals.

Fig 1: Measuring Resistance Between Rear Oxygen Sensor Terminals
Courtesy of SUBARU OF AMERICA, INC.

Terminal No.	Standard
1 and 2	5.6+0.8 -0.6 Ω (when 20°C (68°F))