Diagnostic Test

1) DTC IS ACTIVE
Turn the ignition on.

With a scan tool, select View DTCs. Record DTC and Freeze Frame information.

Start the engine and allow it to idle for at least 60 seconds.

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) (K43) O2 2/1 SIGNAL CIRCUIT
Turn the ignition off.

Disconnect the 2/1 Oxygen Sensor harness connector.

Turn the ignition on.

With a scan tool, read the 2/1 Oxygen Sensor voltage.

Is the 2/1 Oxygen Sensor voltage above 4.8 volts?

Yes
1. Go to step 3).
No
1. Go to step 5).
3) 2/1 OXYGEN SENSOR

Fig 1: Checking O2 Sensor Circuit
Courtesy of CHRYSLER LLC

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

Is the voltage at 2.5 volts?

Yes
1. Verify that there is good pin to terminal contact in the Sensor and Control Module connectors. If OK, replace the 2/1 O2 Sensor.
2. Perform PCM VERIFICATION TEST .
No
1. Go to step 4).
4) (K902) O2 RETURN (UP) CIRCUIT SHORTED TO GROUND

Fig 2: Checking O2 Sensor Circuit
Courtesy of CHRYSLER LLC

Turn the ignition off.

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

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 5).
5) (K43) O2 2/1 SIGNAL CIRCUIT SHORTED TO GROUND

Fig 3: Checking O2 Sensor Circuit
Courtesy of CHRYSLER LLC

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) (K43) O2 2/1 SIGNAL CIRCUIT SHORTED TO THE (K902) O2 RETURN (UP) CIRCUIT

Fig 4: Checking O2 Sensor Circuit
Courtesy of CHRYSLER LLC

Measure the resistance between the (K43) O2 2/1 Signal circuit 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 between the (K43) O2 2/1 Signal circuit and the (K902) O2 Return (Up) circuit.
2. Perform PCM VERIFICATION TEST .
No
1. Go to step 7).
7) POWERTRAIN CONTROL MODULE (PCM)
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.

Verify that there is good pin to terminal contact in the 2/1 O2 Sensor and Powertrain Control Module connectors.

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 and program the Powertrain Control Module (PCM) in accordance with the Service Information.
2. Perform PCM VERIFICATION TEST .