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Oxygen Sensor

For Oxygen (O2) sensor testing, perform appropriate O2 sensor diagnostic test. See the following:

On 4.7L, see DIAGNOSTIC TROUBLE CODE DEFINITIONS in SELF-DIAGNOSTICS - DURANGO - 4.7L article.
On 5.9L, see DIAGNOSTIC TROUBLE CODE DEFINITIONS in SELF-DIAGNOSTICS - DURANGO - 5.9L article.