2000 - 2999: 2950

2950-EGR COOLER

For a complete wiring diagram Consult Diagrams/Electrical

- When Monitored:
With the ignition on and the EGR Solenoid command on.

- Set Condition:
The Engine Control Module (ECM) detects that the EGR Solenoid is obstructed based on exhaust temperature readings.





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

Diagnostic Test

1. DTC IS ACTIVE
Ignition on, engine not running.
With the scan tool, Clear DTCs in the Engine Control Module (ECM).
With the scan tool, actuate the EGR Solenoid.
Monitor the scan tool for at least two minutes.
Start the engine.
With the scan tool, select View DTCs.
Is the status Active for this DTC?

Yes

- Go To 2

No

- Refer to the *CHECKING FOR AN INTERMITTENT DTC Diagnostic Procedure.Component Tests and General Diagnostics

2. EGR SOLENOID CONTROL CIRCUIT SHORTED TO VOLTAGE
Turn the ignition off.
Disconnect the EGR Solenoid harness connector.
Disconnect the Engine Control Module harness connector.
Remove the ASD Relay from the PDC.
Connect a jumper wire between cavity 30 and cavity 87 of the ASD Relay Connector.
Turn the ignition on.
Measure the voltage of the EGR Solenoid Control circuit in the EGR Solenoid harness connector.
Is there any voltage present?

Yes

- Repair the EGR Solenoid Control circuit for a short to voltage.
- Perform the *ECM VERIFICATION TEST VER. 1.Verification Tests

No

- Go To 3

3. EXHAUST GAS TEMPERATURE SENSOR INSPECTION
Turn the ignition off.
Disconnect the Exhaust Gas Temperature Sensor harness connector.
Remove the Exhaust Gas Temperature Sensor.
Inspect the sensor for excessive soot built up or other types of contamination.
Is the temperature excessively dirty?

Yes

- Repair the Exhaust Gas Temperature Sensor.
- Perform the *ECM VERIFICATION TEST VER. 1.Verification Tests

No

- Go To 4

4. EXHAUST TEMPERATURE SENSOR
Turn the ignition on.
With the scan tool, clear DTCs.
With the scan tool, select View DTCs.

NOTE: The scan tool should display an Exhaust Temperature Sensor high voltage or open circuit DTC with the Exhaust Temperature Sensor connector disconnected.

Does the scan tool display the DTC(s) as described above?

Yes

- Replace the Exhaust Temperature Sensor.
- Perform the *ECM VERIFICATION TEST VER. 1.Verification Tests

No

- Go To 5

5. EGR SOLENOID CONTROL CIRCUIT SHORTED TO THE FUSED ASD RELAY OUTPUT CIRCUIT
Turn the ignition off.
Remove the jumper wire and install the ASD relay.
Measure the resistance between the EGR Solenoid Control circuit and the Fused ASD Relay Output circuit in the EGR Solenoid harness connector.
Is the resistance above 1000 ohms?

Yes

- Go To 6

No

- Repair the EGR Solenoid Control circuit for a short to the Fused ASD Relay Output circuit.
- Perform the *ECM VERIFICATION TEST VER. 1.Verification Tests

6. EGR SOLENOID CONTROL CIRCUIT OPEN OR HIGH RESISTANCE
Measure the resistance of the EGR Solenoid Control circuit between the EGR Solenoid harness connector and the Engine Control Module (ECM) harness connector.
Is the resistance below 10.0 ohms?

Yes

- Go To 7

No

- Repair the EGR Solenoid Control circuit for an open circuit or high resistance.
- Perform the *ECM VERIFICATION TEST VER. 1.Verification Tests

7. EGR SOLENOID CONTROL CIRCUIT SHORTED TO GROUND
Measure the resistance between ground and the of the EGR Solenoid Control circuit at the EGR Solenoid harness connector.
Is the resistance below 100 kOhms?

Yes

- Repair the short to ground in the EGR Solenoid Control circuit.
- Perform the *ECM VERIFICATION TEST VER. 1.Verification Tests

No

- Go To 8

8. EGR VALVE
Connect the Engine Control Module (ECM) connector.
Replace the EGR Valve.
Turn the ignition on.
With the scan tool, Clear DTCs.
With the scan tool, actuate the EGR Solenoid.
Monitor the scan tool for at least two minutes.
With the scan tool, select View DTCs.
Is the status Active for this DTC?

Yes

- Go To 9

No

- Test Complete.
- Perform the *ECM VERIFICATION TEST VER. 1.Verification Tests

9. ENGINE CONTROL MODULE (ECM)
Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the EGR Solenoid and the Engine Control Module (ECM).
Look for any chafed, pierced, pinched, or partially broken wires.
Look for broken, bent, pushed out or corroded terminals.
Search for any Technical Service Bulletins that may apply.
Were any problems found?

Yes

- Repair as necessary.
- Perform the *ECM VERIFICATION TEST VER. 1.Verification Tests

No

- Replace the Engine Control Module (ECM).
- Perform the *ECM VERIFICATION TEST VER. 1.Verification Tests