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Home >> Saturn >> 1993 >> SW1 Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Tests W/Codes - ECM/Pcm >> ECM/Pcm Code Charts >> Code 13: Open Oxygen (O2) Sensor Circuit
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Code 13: Open Oxygen (O2) Sensor Circuit

CODE 13 ECM TERMINAL & CIRCUIT WIRING IDENTIFICATION

Application ECM Terminal Wire Color
O2 Signal J1D09 Purple
O2 Ground J1D10 Tan
NOTE: Test numbers refer to numbers on diagnostic chart.
  1. This tests if problem still exists. Vehicle cannot enter "closed loop" mode if O2 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.
    • O2 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.
    • All conditions have existed for a precalibrated amount of time.
  2. Determines if O2 sensor, wiring or control module is at fault. If wiring is good, grounding O2 sensor wire will cause .45 volt reference supplied by control module to pull low.
  3. This tests O2 sensor circuit wiring. Use only a high impedance (10-megohm minimum) digital voltmeter.
Fig 1: Code 13, Schematic, Open Oxygen (O2) Sensor Circuit
G91H07378
Fig 2: Code 13, Flow Chart, Open Oxygen (O2) Sensor Circuit
G91B07281
Fig 3: Code 13
GB0011448