P22B5

P22B5-O2 SENSOR 1/2 PUMP CELL CURRENT TRIM CIRCUIT OPEN

Special Tools:









For a complete wiring diagram, refer to the Wiring Information.
Theory of Operation

The engine after treatment system monitors the oxygen content in the exhaust. The Powertrain Control Module (PCM) monitors the exhaust gases for oxygen content and varies the fuel injector on time to control the intake air fuel mixture. This diagnostic checks to make sure that the oxygen content matches the expected oxygen content for the engine operating conditions. The PCM will set the fault if it detects that the actual oxygen level measurement does not match the expected value. The PCM will illuminate the MIL lamp immediately when the diagnostic runs and fails. The PCM will turn off the MIL lamp diagnostic runs and passes in four consecutive drive cycles.

- When Monitored:
This diagnostic runs when the engine is running.

- Set Condition:
The Powertrain Control Module (PCM) will set the fault if it receives an FMI (Failure Mode Indicator) message from the Smart O2 Sensor Module.





Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Pre-Diagnostic Troubleshooting Procedure.

NOTE: Before replacing O2 Sensor or O2 Sensor Module, check after treatment wiring harness for spread terminals. For wiring harness checking procedure, DO NOT back probe, use Electric Terminal Tool Kit.

1. ACTIVE DTC
1. Turn the ignition on.
2. With the scan tool, record all Freeze frame data.
3. With the scan tool, erase DTCs.
4. Turn the ignition off for 75 seconds.
5. Start the engine and let idle up to five minutes.
6. With the scan tool, read DTCs.

Did the DTC return?

Yes

- Go To 2

No

- Perform the INTERMITTENT CONDITION diagnostic procedure. Intermittent Condition Test

2. CHECK THE (K733) O2 SENSOR 1/2 PUMP CELL CURRENT TRIM CIRCUIT FOR AN OPEN/HIGH RESISTANCE
1. Turn the ignition off.
2. Disconnect the O2 Sensor 1/2 harness connector.
3. Disconnect the Smart O2 Sensor Module harness connector.
4. Measure the resistance of the (K733) O2 Sensor 1/2 Pump Cell Current Trim circuit between the O2 Sensor 1/2 harness connector and the Smart O2 Sensor Module harness connector.

Is the resistance below 5.0 Ohms?

Yes

- Go To 3

No

- Repair the (K733) O2 Sensor 1/2 Pump Cell Current Trim circuit for an open or high resistance.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test.

3. OXYGEN SENSOR SOOTED
1. Remove the O2 Sensor 1/2.
2. Carefully clean the soot from the O2 Sensor.

NOTE: Do not tap or bang the sensor to remove loose debris. This will damage the sensor.

3. Reinstall the O2 Sensor 1/2.
4. With the scan tool, erase DTCs.
5. Turn the ignition off for 75 seconds.
6. Start the engine and let idle for up to five minutes.
7. With the scan tool, read DTCs.

Did the DTC return?

Yes

- Go To 4

No

- Repair complete.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test.

4. SMART O2 SENSOR MODULE
1. Remove the O2 Sensor 1/2 and O2 Sensor 1/1.
2. Install the O2 Sensor 1/2 in the O2 Sensor 1/1 position.
3. Install the O2 Sensor 1/1 in the O2 Sensor 1/2 position.
4. With the scan tool, erase DTCs.
5. Turn the ignition off for 75 seconds.
6. Start the engine and let idle for two minutes.
7. With the scan tool, read DTCs.

Did the DTC change to P2626?

Yes

- Reinstall O2 Sensor 1/1 back to it's original position and replace the O2 Sensor 1/2.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test.

No

- Replace the Smart O2 Sensor Module. Return the O2 Sensors back to their original positions.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test.