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Home >> Dodge and Ram >> 1998 >> Durango 5.9 Z, Part Time >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Tests W/Codes - Engine Performance >> Self-Diagnostic Tests >> Test TC-122A: 2/1 O2 Sensor Slow Response
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Test TC-122A: 2/1 O2 Sensor Slow Response

NOTE: This test applies to AN body (2WD) equipped with 5.9L engine, and BE/BR bodies equipped with 5.9L heavy-duty engine or 8.0L engine only. For connector terminal identification, see CONNECTOR IDENTIFICATION . For component location and wiring diagram, see WIRING DIAGRAMS article.
  1. O2 SENSOR SLOW RESPONSE DTC sets if 2/1 Heated Oxygen Sensor (HO2S) voltage is switches from less than 0.27 volt to more than 0.62 volt fewer times than required. Possible causes are: exhaust leak, fuel contamination, HO2S heater failure, defective O2S, defective wiring or connectors, or engine mechanical problems. Go to next step.
  2. Start engine. Check exhaust system for leaks between engine and catalytic converter. Repair exhaust system as necessary and perform TEST VER-5A: ROAD TEST FOR OBD-II TROUBLE CODES . If exhaust system is okay, go to next step.
  3. Check exhaust for excessive smoke caused by oil or coolant consumption. Repair engine mechanical condition as necessary, replace catalytic converter and HO2Ss, and perform TEST VER-5A: ROAD TEST FOR OBD-II TROUBLE CODES . If engine mechanical condition is okay, go to next step.
  4. Turn ignition off. Disconnect 2/1 HO2S connector. Inspect connector and terminals for damage. Repair connector and terminals as necessary and perform TEST VER-5A: ROAD TEST FOR OBD-II TROUBLE CODES . If connector and terminals are okay, go to next step.
  5. Using an external ohmmeter, check resistance between ground and 2/1 HO2S connector, sensor ground circuit (Black/Light Blue wire). If resistance is 5 ohms or more, repair open sensor ground circuit and perform TEST VER-5A: ROAD TEST FOR OBD-II TROUBLE CODES . If resistance is less than 5 ohms, go to next step.
  6. Disconnect Powertrain Control Module (PCM) connectors. Inspect connectors and terminals for damage. Repair connectors and terminals as necessary and perform TEST VER-5A: ROAD TEST FOR OBD-II TROUBLE CODES . If connectors and terminals are okay, replace 2/1 HO2S and perform TEST VER-5A: ROAD TEST FOR OBD-II TROUBLE CODES .
NOTE: A break in test sequence occurs at this point. Sequence skips from TEST TC-122A to TEST TC-124A. No tests have been omitted.
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