Diagnostic Test

1) DTC IS ACTIVE
NOTE: If an O2 sensor signal circuit is shorted to voltage, all O2 sensor voltage readings displayed on the scan tool will be approximately 5.0 volts. Diagnose the sensor that set the most current DTC.

NOTE: After repairs have been completed, verify proper O2 Sensor operation. If all O2 Sensor voltage readings have not returned to normal, perform the diagnostic procedure for the remaining O2 Sensors.

NOTE: It may be necessary to test drive the vehicle within the DTC monitoring conditions in order for this DTC to set.

Start the engine and allow it to reach operating temperature.

WARNING: When the engine is operating, do not stand in direct line with the fan. Do not put your hands near the pulleys, belts, or fan. Do not wear loose clothing. Failure to follow these instructions can result in personal injury or death.

With a scan tool, select View DTCs.

Is the DTC Active at this time?

Yes
1. Go to step 2).
No
1. Refer to *CHECKING FOR AN INTERMITTENT DTC diagnostic procedure.

2) CHECKING THE EXHAUST SYSTEM FOR LEAKS

Turn the ignition off.

Raise the vehicle in accordance with the Service Information.

WARNING: The normal operating temperature of the exhaust system is very high. Never work around or attempt to service any part of the exhaust system until it has cooled. Special care should be taken when working near the catalytic converter. The temperature of the converter rises to a high level after a short period of engine operating time

Connect Exhaust Cone #8404-EC or #8404-EC to Air Pressure Regulator (with hose) #W-18-MIL-1146AS.

CAUTION: The air pressure must not exceed 27.6 kPa (4 psi), otherwise engine damage can occur.

Attach shop air to the air pressure regulator.

Adjust the Air Pressure Regulator to 27.6 kPa (4 psi)

Insert the exhaust cone into the vehicle tail pipe.

If the vehicle is equipped with dual exhaust. Use the #8404-ECT with equipped attached plug, plug one side of the dual exhaust pipe. Pressurize the other as described above.

Apply Mopar® Air Leak Detector PN# 05191804AA (or an equivalent leak finder liquid) to the following areas:

- All welded joints from the exhaust manifold to 152.4 mm (6 inches) behind the downstream O2 sensor

- O2 sensor seal points

- O2 sensor boss welds

- Flange/joint connection(s)

- Exhaust manifold to cylinder head connection(s)

- EGR solenoid gasket base and tube seal points (if equipped)

Watch for the liquid/soapy water to bubble.

Use the following definitions to help determine if system or component repair/replacement is necessary:

Type 1 Leak is defined as a leak where very small foam like bubbles 1 mm (0.04 of an inch) or less appear.

Any Type 1 or greater leaks found in welded joints, O2 sensor seal points or O2 sensor boss welds must be repaired or the component must be replaced.

Type 2 Leak is defined as a leak where larger bubbles pea size, 8 mm (0.3 of an inch) or greater appear.

Any Type 2 or greater leaks found in flange or joint connections, exhaust manifold to cylinder head connections, or EGR gasket and tube seal points must be repaired or the components must be replaced.

Leak Location	Repair required if results at 27.6 kPa (4 psi) reveal bubble size:
Welded joints	Type 1, 1 mm (0.04 of an inch) or greater
O2 Sensor seal points	Type 1, 1 mm (0.04 of an inch) or greater
O2 Sensor boss welds	Type 1, 1 mm (0.04 of an inch) or greater
Flange / joint connections	Type 2, 8 mm (0.3 of an inch) or greater
Exhaust Manifold to cylinder head connections	Type 2, 8 mm (0.3 of an inch) or greater
EGR gasket and tube seal points	Type 2, 8 mm (0.3 of an inch) or greater

If a leak is found that matches the above definition, repair or replace the component as necessary.

Once the repair is complete, repeat the procedure to verify that all leaks have been repaired.

Were any exhaust leaks found?

Yes

Repair or replace the leaking exhaust parts as necessary.
Perform PCM VERIFICATION TEST .

Go to step 3).

3) (K43) O2 2/1 SIGNAL CIRCUIT SHORTED TO VOLTAGE

Fig 1: Checking O2 Sensor Circuit
Courtesy of CHRYSLER LLC

Turn the ignition off.

Disconnect the 2/1 Oxygen Sensor harness connector.

Disconnect the C2 and C3 Powertrain Control Module (PCM) harness connectors.

Turn the ignition on.

Measure the voltage of the (K43) O2 2/1 Signal circuit in the 2/1 Oxygen Sensor harness connector.

NOTE: Measure the voltage in reference to ground, not the (K902) O2 Return (Up) circuit.

Is there any voltage present?

Yes
1. Repair the short to voltage in the (K43) O2 2/1 Signal circuit.
2. Perform PCM VERIFICATION TEST .
No
1. Go to step 4).
4) (K902) O2 RETURN (UP) CIRCUIT SHORTED TO VOLTAGE

Fig 2: Checking O2 Sensor Circuit
Courtesy of CHRYSLER LLC

Measure the voltage of the (K902) O2 Return (Up) circuit in the 2/1 Oxygen Sensor harness connector.

Is there any voltage present?

Yes
1. Repair the short to voltage in the (K902) O2 Return (Up) circuit.
2. Perform PCM VERIFICATION TEST .
No
1. Go to step 5).
5) (K43) O2 2/1 SIGNAL CIRCUIT SHORTED TO GROUND

Fig 3: Checking O2 Sensor Circuit
Courtesy of CHRYSLER LLC

Turn the ignition off.

Measure the resistance between ground and the (K43) O2 2/1 Signal circuit in the 2/1 Oxygen Sensor harness connector.

Is the resistance below 100 ohms?

Yes
1. Repair the short to ground in the (K43) O2 2/1 Signal circuit.
2. Perform PCM VERIFICATION TEST .
No
1. Go to step 6).
6) (K902) O2 RETURN (UP) CIRCUIT SHORTED TO GROUND

Fig 4: Checking O2 Sensor Circuit
Courtesy of CHRYSLER LLC

Measure the resistance between ground and the (K902) O2 Return (Up) circuit in the 2/1 Oxygen Sensor harness connector.

Is the resistance below 100 ohms?

Yes
1. Repair the short to ground in the (K902) O2 Return (Up) circuit.
2. Perform PCM VERIFICATION TEST .
No
1. Go to step 7).
7) EXCESSIVE RESISTANCE IN THE (K43) O2 2/1 SIGNAL CIRCUIT

Fig 5: Checking O2 Sensor Circuit
Courtesy of CHRYSLER LLC

CAUTION: Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals, resulting in poor terminal to pin connection. Install Miller Special Tool #8815 to perform diagnosis.

Measure the resistance of the (K43) O2 2/1 Signal circuit between the 2/1 Oxygen Sensor harness connector and the appropriate terminal of special tool #8815.

Is the resistance below 5.0 ohms?

Yes
1. Go to step 8).
No
1. Repair the excessive resistance in the (K43) O2 2/1 Signal circuit.
2. Perform PCM VERIFICATION TEST .
8) EXCESSIVE RESISTANCE IN THE (K902) O2 RETURN (UP) CIRCUIT

Fig 6: Checking O2 Sensor Circuit
Courtesy of CHRYSLER LLC

Measure the resistance of the (K902) O2 Return (Up) circuit between the 2/1 Oxygen Sensor harness connector and the appropriate terminal of special tool #8815.

Is the resistance below 5.0 ohms?

Yes
1. Go to step 9).
No
1. Repair the excessive resistance in the (K902) O2 Return (Up) circuit.
2. Perform PCM VERIFICATION TEST .
9) 2/1 OXYGEN SENSOR
NOTE: Check for signs of contaminants that may have damaged the O2 Sensor, such as contaminated fuel, unapproved silicone, oil and coolant.

Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the 2/1 Oxygen Sensor and the Powertrain Control Module (PCM).

Look for any chafed, pierced, pinched, or partially broken wires.

Look for broken, bent, pushed out or corroded terminals.

Refer to any Technical Service Bulletins that may apply.

Were any problems found?

Yes
1. Repair as necessary.
2. Perform PCM VERIFICATION TEST .
No
1. Replace the 2/1 Oxygen Sensor in accordance with the Service Information.
2. Perform PCM VERIFICATION TEST .