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Code 13 - Open Oxygen Sensor Circuit: Notes

NOTE: The 5.7L (VIN P) engine is equipped with 2 oxygen sensors. On these models, Code 13 will set if the left sensor circuit is open. Code 63 will set if the right sensor circuit is open. Use this chart for Code 63 also and perform tests for applicable sensor.
NOTE: Test numbers refer to numbers on diagnostic chart.
  1. This tests if problem still exists. Vehicle cannot enter "closed loop" mode if oxygen sensor circuit is open. Code 13 indicates an open in O2 sensor circuit. Code will set if Engine is at normal operating temperature, neither Code 21 nor Code 22 is stored, oxygen sensor voltage is constant within a specified range (.34-.55 volt), throttle angle is greater than idle, a precalibrated amount of time has elapsed since start-up and all conditions have existed for a precalibrated amount of time.
  2. Determines if oxygen sensor, wiring or control module is at fault. If wiring is good, grounding oxygen sensor wire will cause .45 volt reference supplied by control module to pull low.
  3. This tests oxygen sensor circuit wiring. Use only a high impedance (10-megohm minimum) digital voltmeter.