This bulletin involves repositioning the upstream oxygen (O2) sensor connectors and replacing the wiring harness connector(s) and O2 sensor(s) as necessary.

Models affected: 2005-’06 (LX) 300/Magnum/Charger

Note: This bulletin applies to vehicles equipped with a 2.7L, 3.5L or 5.7L engine (sales code EER, EGG or EZB).

Symptom/Condition
MIL illumination due to one or more of the following DTCs:
• P0037-O2 Sensor 1/2 Heater Circuit Low
• P0058-O2 Sensor 2/2 Heater Circuit High
• P0131-O2 Sensor 1/1 Circuit Low
• P0132-O2 Sensor 1/1 Circuit High
• P0133-O2 Sensor 1/1 Slow Response
• P0138-O2 Sensor 1/2 Circuit High
• P0151-O2 Sensor 2/1 Circuit Low
• P0153-O2 Sensor 2/1 Slow Response
• P0159-O2 Sensor 2/2 Slow Response

The condition may be due to the cowl drain flowing water onto the connectors for the O2 sensor(s) at the center rear area of the engine. This leads to water intrusion into the wiring harness connector(s), which may lead to terminal corrosion and/or MIL illumination.

Diagnosis

Note: If the vehicle is equipped with a 5.7L engine (sales code EZB) and was built on or before Aug. 18, 2004 (MDH 0818XX), perform Service Bulletin 18-031-04 REV A as necessary before continuing with diagnosis. For 2.7L and 3.5L engines, continue with the diagnosis.

1. Open the hood

2. Disconnect the O2 sensor connectors and check for water intrusion and/or corrosion in both upstream O2 sensor connectors at the center rear area of the engine.

a. If no water or corrosion is present, reposition the wiring harness connectors to the outboard edge of the valve cover away from the center of the engine. Tie-strap the harnesses in place. If no water or corrosion was present, further diagnosis is required. This bulletin does not apply.

b. If water is present but no corrosion, blow out the connector(s) and reposition the wiring harness to the outboard edge of the valve cover away from the center of the engine. Tie-strap the harness in place.

c. If corrosion is present, perform the Repair Procedure.

Repair Procedure
2.7L and 3.5L Engines Replace O2 Sensor and Wiring Harness ­Connector

1. Remove the appropriate O2 sensor. Note: It may be necessary to disconnect the purge vacuum
harness to gain better access to the harness connectors.

2. Replace the wiring harness connector, using kit P/N 05161925AA.

3. Install the new O2 sensor using the appropriate part number.

4. Reposition the wiring harness connectors to the outboard edge of the valve cover away from the
center of the engine. Tie-strap the harnesses in place.

5.7L Engine Replace O2 Sensor and Wiring Harness Connector

1. Release fuel pressure.

Warning: The fuel system is under constant pressure even with engine off. Before servicing the fuel rail, the fuel system pressure must be released.

2. Disconnect the negative battery cable.

3. Remove the intake manifold.

4. Remove the three engine harness retaining clips from the engine harness bracket.

5. Disconnect and remove the appropriate O2 sensor.

6. Pull the lower harness up to access the O2 harness connectors.

7. Replace the wiring harness connector, using kit P/N 05161925AA.

8. Install the new O2 sensor using the appropriate part number.

9. Reposition the wiring harness connectors to the outboard edge of the valve cover away from the
center of the engine. Tie-strap the harnesses in place.

Courtesy of Identifix.