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Home >> Chevrolet >> 1995 >> Corvette ZR-1 >> Repair and Diagnosis >> External Pages >> Different variant/trim >> Section 2 (Engine Controls - Tests W/Codes) >> ECM/Pcm Code Charts >> Code 13, Open Oxygen Sensor Circuit >> Test Description
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Test Description

WARNING: This page is about a different variant/trim than selected.
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 indicates an open in O2 sensor circuit (steady .35-.55 volt).
  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.
Fig 1: Code 13 Schematic (Corvette) Open Oxygen Sensor Circuit
G91H07378
Fig 2: Code 13 Diagnostic Flow Chart (Corvette) Open Oxygen Sensor Circuit
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