P245D

P245D-EGR COOLER BYPASS CONTROL CIRCUIT HIGH





For a complete wiring diagram Refer to Diagrams/Electrical.

Theory of Operation


The signal line is the command from the ECM to the bypass valve. If this line is shorted high the bypass valve be bypassing the cooler. EGR orifice temperatures will increase. This is a high side driver. There is no action taken if this fault goes active.

- When Monitored:
Key on

- Set Condition:
When EGR Cooler Bypass valve is in cooler bypass mode and signal line is higher than a calibrated threshold.







Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Initial Inspection and Diagnostic Overview


1. P245D ACTIVE
Ignition on, engine not running.
With the scan tool, read DTC's.
Is DTC P245D active?

Yes


- Go To 2


No


- Repair the intermittent condition.
- Refer to the INTERMITTENT CONDITION - DIESEL Symptom. Intermittent Condition



2. (K670) SIGNAL CIRCUIT SHORTED TO ANOTHER CIRCUIT




Turn the ignition off.
Disconnect the C1 ECM harness connector.
Disconnect the EGR Cooler Bypass valve harness connector.

NOTE: Check connectors - Clean/repair as necessary.

Measure the resistance between the (K670) EGR Cooler Bypass Valve signal circuit in the engine harness C1 ECM connector and all other circuits in the ECM connector.
Is the resistance greater than 100k ohms?

Yes


- Go To 3


No


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



3. P245D ACTIVE
Reconnect all harnesses.
Ignition on, engine not running.
With the scan tool, read DTC's.
Is P245D active?

Yes


- Go To 4


No


- Repair complete.



4. ECM




Turn the ignition off.
Disconnect the EGR Cooler Bypass valve harness connector.

NOTE: Check connectors - Clean/repair as necessary.

Use a jumper wire to connect the (K670) EGR bypass signal circuit to 12-volts.
Turn the ignition on.
With the scan tool, read DTC's.
Did P245D go inactive?

Yes


- Replace the EGR Bypass Valve.
- Perform POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test


No


- Replace ECM.
- Replace and program the Engine Control Module Engine Control Module