2000 - 2999: 2978

2978-EXHAUST GAS COOLER ACTUATOR - OPEN CIRCUIT

For a complete wiring diagram, Refer to the Wiring Information Electrical Diagrams.

- When Monitored:
With the ignition on and the Exhaust Gas Cooler Actuator commanded on.

- Set Condition:
The Engine Control Module (ECM) detects an open circuit Exhaust Gas Cooler Actuator.





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

1. DTC IS ACTIVE
1. Ignition on, engine not running.
2. With the scan tool, monitor and record the freeze frame data.
3. With the scan tool, clear DTCs in the Engine Control Module.
4. Start the engine.
5. Operate the engine in the conditions that the DTC was set.
6. With the scan tool, select View DTCs.

Is the status Active for this DTC?

Yes

- Go To 2

No

- Perform the INTERMITTENT DTC diagnostic procedure. .

2. EXHAUST GAS COOLER ACTUATOR SUPPLY CIRCUIT OPEN/HIGH RESISTANCE
1. Turn the ignition off.
2. Disconnect the Exhaust Gas Cooler Actuator harness connector.
3. Turn the ignition on.
4. Using a voltmeter, measure the voltage at the Exhaust Gas Cooler Actuator Power Supply circuit at the Exhaust Gas Cooler Actuator harness connector.

Is the voltage between 11.0 and 14.0 Volts?

Yes

- Go To 3

No

- Repair the Exhaust Gas Cooler Actuator Power Supply circuit for an open or high resistance.
- Perform the ECM Verification Test. Verification Tests.

3. EXHAUST GAS COOLER ACTUATOR CONTROL CIRCUIT OPEN/HIGH RESISTANCE
1. Turn the ignition off.
2. Disconnect the ECM harness connector.
3. Measure the resistance of the Exhaust Gas Cooler Actuator Control circuit between the ECM harness connector and the Exhaust Gas Cooler Actuator harness connector.

Is the resistance below 1.0 Ohm?

Yes

- Go To 4

No

- Repair the Exhaust Gas Cooler Actuator Control circuit for an open or high resistance.
- Perform the ECM Verification Test. Verification Tests.

4. EXHAUST GAS COOLER ACTUATOR
1. Measure the resistance of the Exhaust Gas Cooler Actuator.

Is the resistance between 28.0 and 32.0 Ohms?

Yes

- Go To 5

No

- Replace the Exhaust Gas Cooler Actuator.
- Perform the ECM Verification Test. Verification Tests.

5. ENGINE CONTROL MODULE
1. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the EGR Solenoid and the Engine Control Module.
2. Look for any chafed, pierced, pinched, or partially broken wires.
3. Look for broken, bent, pushed out or corroded terminals.
4. Perform any Technical Service Bulletins that may apply.

Were any problems found?

Yes

- Repair as necessary.
- Perform the ECM Verification Test. Verification Tests.

No

- Replace the Engine Control Module.
- Perform the ECM Verification Test. Verification Tests.