P245B

P245B-EGR COOLER BYPASS STATUS LINE INTERMITTENT




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

The Exhaust Gas Recirculation (EGR) Cooler Bypass Valve is used to redirect the EGR gases around the cooler when the engine is under certain operating conditions. The EGR Cooler Bypass Valve is a smart device which communicates it's status to the Powertrain Control Module (PCM). At key on the EGR Cooler Bypass Valve drives the signal line low and then high and the PCM monitors for the correct status response from the EGR Cooler Bypass Valve. Throughout engine operation the PCM sends commands via the signal circuit to the EGR Cooler Bypass Valve and monitors the status line to confirm that the EGR Cooler Bypass Valve has reached the commanded position. When a fault occurs, the EGR Cooler Bypass valve will send a signal of less than one Volt on the status line to the PCM. The PCM will light a MIL lamp after this monitor runs and fails in two consecutive drive cycles. The PCM will turn off the MIL lamp after the diagnostic passes in four consecutive drive cycles.

- When Monitored:
With the ignition on.

- Set Condition:
Voltage detected at status line is below 1.0 Volt for more than 20 seconds consecutively.





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

1. ACTIVE DTC

NOTE: If DTC P245C, P245D, P144E, OR P144F are present, perform those test procedures before proceeding.

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. Turn the ignition on.
6. With the scan tool, read DTCs.

Did the DTC return?

Yes

- Go To 2

No

- Perform the INTERMITTENT CONDITION - 6.7L diagnostic procedure. Intermittent Condition Test

2. CHECK THE (K671) EGR COOLER BYPASS VALVE STATUS LINE FOR AN OPEN/HIGH RESISTANCE
1. Turn the ignition off.
2. Disconnect the EGR Cooler Bypass Valve harness connector.
3. Disconnect the PCM C1 harness connector.
4. Measure the resistance of the (K671) EGR Cooler Bypass Valve Status Line between the EGR Cooler Bypass Valve harness connector and the PCM C1 harness connector.

Is the resistance below 5.0 Ohms?

Yes

- Go To 3

No

- Repair the (K671) EGR Cooler Bypass Valve Status Line for an open or high resistance.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test.

3. EGR COOLER BYPASS VALVE
1. Replace the EGR Cooler Bypass Valve.
2. Turn the ignition on.
3. With the scan tool, erase DTCs.
4. Start the engine and test drive the vehicle.
5. With the scan tool, read DTCs.

Did the DTC return?

Yes

- Replace the Powertrain Control Module.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test.

No

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