P245A
P245A-EGR COOLER BYPASS CONTROL CIRCUIT/OPEN
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 between 1.0 Volt and 1.7 Volts for more than 150 seconds consecutively.
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Pre-Diagnostic Troubleshooting Procedure.
1. ACTIVE DTC
NOTE: A faulty EGR Outlet Temperature Sensor can cause this DTC to set. Repair any EGR Outlet Temperature Sensor DTCs before proceeding.
NOTE: If DTC P245C or P245D 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 (F344) SMART POWER RELAY FEED CIRCUIT
1. Turn the ignition off.
2. Disconnect the EGR Cooler Bypass Valve harness connector.
3. Turn the ignition on.
4. Measure the voltage on the (F344) Smart Power Relay Feed circuit at the EGR Cooler Bypass Valve harness connector.
Is the voltage equal to battery voltage?
Yes
- Go To 3
No
- Repair the (F344) Smart Power Relay Feed circuit for an open or short to ground.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test.
3. CHECK THE (K670) EGR COOLER BYPASS VALVE SIGNAL CIRCUIT FOR AN OPEN/HIGH RESISTANCE
1. Turn the ignition off.
2. Disconnect the PCM C1 harness connector.
3. Measure the resistance of the (K670) EGR Cooler Bypass Valve Signal circuit between the EGR Cooler Bypass Valve harness connector and the PCM C1 harness connector.
Is the resistance below 5.0 Ohms?
Yes
- Go To 4
No
- Repair the (K670) EGR Cooler Bypass Valve Signal circuit for an open or high resistance.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test.
4. CLEAN THE EGR COOLER
1. Remove and clean the EGR Cooler and EGR Outlet Temperature Sensor.
2. Reinstall the EGR Cooler and EGR Outlet Temperature Sensor.
3. Turn the ignition on.
4. With the scan tool, erase DTCs.
5. Start the engine and test drive the vehicle.
6. With the scan tool, read DTCs.
Did the DTC return?
Yes
- Go To 5
No
- Repair complete.
- Perform the DIESEL AFTERTREATMENT VALIDATION - 6.7L. Component Tests and General Diagnostics
5. 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 DIESEL AFTERTREATMENT VALIDATION - 6.7L. Component Tests and General Diagnostics