LEMON Manuals: Even more car manuals for everyone: 1960-2025
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-189A: 1/3 O2 Sensor Heater Failure
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Test TC-189A: 1/3 O2 Sensor Heater Failure

NOTE: This test applies to AN body (2WD) equipped with 5.9L engine and BE/BR bodies equipped with 8.0L medium-duty engine only. For connector terminal identification, see CONNECTOR IDENTIFICATION . For component location and wiring diagram, see WIRING DIAGRAMS article.
CAUTION: Allow Heated Oxygen Sensor (HO2S) to cool to room temperature before checking resistance.
NOTE: 1/3 HO2S is located in post-catalyst position.
  1. Using scan tool, read DTCs. Repair any other 1/3 HO2S related DTCs before proceeding. If no other 1/3 HO2S DTCs are present, go to next step
  2. Turn ignition on, engine off. Wait 3 minutes. Using scan tool in SENSORS, monitor 1/3 HO2S voltage. Wait for voltage to stabilize at more than 4.5 volts. Go to next step.
  3. Using scan tool in ACTUATOR TESTS, perform HO2S heater test. Monitor 1/3 HO2S voltage for 2 minutes. If voltage is more than one volt, go to step 5)  . If voltage is one volt or less, go to next step.
  4. Conditions required to set DTC are not present at this time. O2 SENSOR HEATER FAILURE DTC sets if Powertrain Control Module (PCM) senses HO2S voltage at more than 3 volts for 30-90 seconds after a cold engine start. Possible causes are: open HO2S heater element circuit, HO2S failure, HO2S heater wiring failure, PCM failure, defective connections or wiring. Stop all actuator tests. Test is complete. Perform TEST VER-2A: ROAD TEST VERIFICATION .
  5. Disconnect 1/3 HO2S connector. Inspect connector and terminals for damage. Repair connector and terminals as necessary and perform TEST VER-2A: ROAD TEST VERIFICATION . If connector and terminals are okay, go to next step.
  6. Ensure scan tool is actuating HO2S heater test. Using an external voltmeter, check voltage on 1/3 HO2S ASD relay output circuit (Dark Green/Orange wire). If voltage is 10 volts or less, repair open ASD relay output circuit and perform TEST VER-2A: ROAD TEST VERIFICATION . If resistance is more than 10 volts, go to next step.
  7. Stop all actuator tests. Using an external ohmmeter, check resistance between HO2S (component side), ASD relay output circuit (White wire) and heater ground circuit (White wire). See Fig 1. If resistance is not 4-7 ohms, replace 1/3 HO2S and perform TEST VER-2A: ROAD TEST VERIFICATION . If resistance is 4-7 ohms, go to next step.
  8. Check resistance between ground and HO2S connector, heater ground circuit (Black/White wire). If resistance is 5 ohms or more, repair open heater ground circuit and perform TEST VER-2A: ROAD TEST VERIFICATION . If resistance is less than 5 ohms, replace 2/1 HO2S and perform TEST VER-2A: ROAD TEST VERIFICATION .
Fig 1: TC-189A: Identifying Heated Oxygen Sensor Connector Terminals (Component Side)
G95J35674
NOTE: A break in test sequence occurs at this point. Sequence skips from TEST TC-189A to TEST TC-192A. No tests have been omitted.
scientia non olet · About LEMON Manuals