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Home >> Dodge and Ram >> 2003 >> Durango Base, 5.9 Z, 4WD, Part Time >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Self-Diagnostics - 5.9L >> Diagnostic Tests >> DTC P0136: O2 Sensor 1/2 Heater Circuit Malfunction >> Testing
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DTC P0136: O2 Sensor 1/2 Heater Circuit Malfunction: Testing

  1. Turn ignition on, with engine off. With the DRBIII® scan tool, read the DTCs and record the related freeze frame data. Is the good trip counter displayed and equal to zero? If yes, go to next step. If no, see INTERMITTENT CONDITION  under SELF-DIAGNOSTIC SYSTEM.
    2. NOTE: O2 sensor heater relay may also be referred to as O2 heater relay or O2 relay.
  2. Turn the ignition off. Remove the heater relay from the PDC. Measurement is taken at the heater relay component. Measure the resistance of the O2 sensor heater relay coil. Is the resistance more than 100 ohms? If yes, replace the O2 sensor heater relay. If no, go to next step.
  3. Turn ignition on, with engine off. With the DRBIII® scan tool, actuate the ASD relay. Using a 12-volt test light connected to ground, probe the (F142) fused ASD relay output circuit of the O2 heater relay in the PDC. Does the test light illuminate brightly when the relay actuates? If yes, go to next step. If no, repair the open or short to ground in the (F142) ASD relay output circuit. Inspect the related fuse and repair as necessary.
  4. Turn the ignition off. Disconnect the PCM harness connectors. Measure the resistance of the (K512) O2 heater relay control circuit from the PDC (heater relay) connector to the PCM harness connector. Is the resistance less than 5.0 ohms? If yes, go to next step. If no, repair the open in the (K512) O2 heater relay control circuit.
  5. Measure the resistance between ground and the (K512) O2 heater relay control circuit at the PDC connector. Is the resistance less than 100 ohms? If yes, repair the short to ground in the (K512) O2 sensor heater relay control circuit. If no, go to next step.
    6. NOTE: Before continuing, disconnect the PCM harness connectors and check the related wiring terminals for corrosion, damage or terminal push out. Repair as necessary.
  6. Using the wiring diagram as a guide, inspect the wire harness and connectors. Visually inspect the related wire harness. Look for any chafed, pierced, pinched, or partially broken wires. Visually inspect both the component and the PCM connectors. Pay particular attention to all power and ground circuits. If there are no possible causes remaining, replace and program the PCM. See PROGRAMMING .
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