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Home >> Infiniti >> 2003 >> QX4 4WD >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Controls - Self-Diagnostics >> Diagnostic Tests >> DTC P1148: Bank 1 Closed Loop Control Not Obtained Or DTC P1168: Bank 2 Closed Loop Control Not Obtained >> DTC Confirmation Test (Using Generic Scan Tool)
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DTC Confirmation Test (Using Generic Scan Tool)

CAUTION: DO NOT use ECM ground terminals when measuring voltage.
NOTE: Use the following test to check overall function of closed loop fuel control. During this test, DTC may not be confirmed.
  1. Start engine and warm to normal operating temperature. Backprobbing at ECM, measure voltage between ground and ECM terminal No. 63 (bank 1) or No. 62 (bank 2). See Figure and Figure .
  2. Monitor voltmeter with engine at 2000 RPM. Voltage should be less than .21 volt at least once and more than .70 volt at least once. If voltage is not as specified, go to DIAGNOSTIC PROCEDURE . If voltage is as specified, system is okay at this time.
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