P02E1 - Diesel Intake Air Flow Control Performance
Theory of Operation
The Exhaust Gas Recirculation (EGR) Airflow Control Valve is controlled by the Powertrain Control Module (PCM) and is actuated by an electric motor. A spring internal to the actuator assembly attempts to drive the valve to the fully-open position. The electric motor works to overcome the spring force when the engine control module commands the valve to close. Position feedback from the valve is sent to the PCM to allow for closed-
loop control. Discrepancy in position feedback sent to the PCM, and commanded position sent to the EGR Airflow Control Valve by more than a prescribed amount will result in failure of device rationality diagnostics. Failure to properly actuate the EGR Airflow Control Valve can result in poor engine performance. This may cause active Exhaust Aftertreatment regenerations to last longer.
When Monitored:
With the ignition on.
Set Condition:
The Powertrain Control Module (PCM) detects that the EGR Airflow Control Valve is sticking or out of calibration.
Possible Causes
AIR INTAKE THROTTLE MOTOR (-) CIRCUIT OPEN/HIGH RESISTANCE
AIR INTAKE THROTTLE MOTOR (-) CIRCUIT OPEN/HIGH RESISTANCE
EGR AIRFLOW CONTROL VALVE
POWERTRAIN CONTROL MODULE (PCM)
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 28 - DTC-
Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).
1. DTC ACTIVE
1. Turn the ignition on.
2. With the scan tool, record all Freeze frame data.
NOTE: If DTC P02E2 or P02E3 are active, perform diagnosis and repair on those DTCs before continuing with this diagnostic tree.
3. With the scan tool, erase DTCs.
4. Turn the ignition off for 75 seconds.
5. Start the engine and let idle for one minute.
6. With the scan tool, read DTCs.
Is DTC P02E1 active?
Yes
• Go To 2
No
• Perform the INTERMITTENT CONDITION diagnostic procedure. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).
2. CHECK THE (K674) AIR INTAKE THROTTLE MOTOR (-) CIRCUIT FOR HIGH RESISTANCE
1.
2. Turn the ignition off.
3. Disconnect the EGR Airflow Control Valve harness connector.
4. Disconnect the PCM C1 harness connector.
NOTE: Check connectors - Clean/repair as necessary.
5. Measure the resistance of the (K674) Air Intake Throttle Motor (-) circuit between the EGR Airflow Control Valve harness connector and the PCM C1 harness connector.
Is the resistance below 5.0 Ohms?
Yes
• Go To 3
No
• Repair the (K674) Air Intake Throttle Motor (-) circuit for an open or high resistance.
• Perform the POWERTRAIN VERIFICATION TEST - 6.7L. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).
3. CHECK THE (K673) AIR INTAKE THROTTLE MOTOR (+) CIRCUIT FOR HIGH RESISTANCE
1.
2. Measure the resistance of the (K673) Air Intake Throttle Motor (+) circuit between the EGR Airflow Control
Valve harness connector and the PCM C1 harness connector.
Is the resistance below 5.0 Ohms?
Yes
• Go To 4
No
• Repair the (K673) Air Intake Throttle Motor (+) circuit for an open or high resistance.
• Perform the POWERTRAIN VERIFICATION TEST - 6.7L. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).
4. EGR AIRFLOW CONTROL VALVE
1. Turn the ignition off.
2. Reconnect the PCM C1 harness connector.
3. Ignition on, engine not running.
4. Using a voltmeter connected to ground, measure the voltage on the:
• (K673) Air Intake Throttle Motor (+) circuit at the EGR Airflow Control Valve harness connector.
• (K674) Air Intake Throttle Motor (-) circuit at the EGR Airflow Control Valve harness connector.
NOTE: The voltage on the control circuits should read approximately battery voltage.
Are both measurements equal to battery voltage?
Yes
• Replace the EGR Airflow Control Valve in accordance with the Service Information.(Refer to 25 - Emissions Control/Exhaust Gas Recirculation, Diesel/VALVE, Exhaust Gas Recirculation (EGR) Airflow Control/Removal)
• Perform the POWERTRAIN VERIFICATION TEST - 6.7L. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).
No
• Go To 5
5. POWERTRAIN CONTROL MODULE
1. Disconnect all PCM harness connectors.
2. Disconnect all related in-line harness connections (if equipped).
3. Disconnect the related component harness connectors.
4. Inspect harness connectors, component connectors, and all male and female terminals for the following conditions:
Proper connector installation.
Damaged connector locks.
Corrosion.
Other signs of water intrusion.
Weather seal damage (if equipped).
Bent terminals.
Overheating due to a poor connection (terminal may be discolored due to excessive current draw).
Terminals that have been pushed back into the connector cavity.
Perform a terminal drag test on each connector terminal to verify proper terminal tension. Repair any conditions that are found.
5. Reconnect all PCM harness connectors. Be certain that all harness connectors are fully seated and the connector locks are fully engaged.
6. Reconnect all in-line harness connectors (if equipped). Be certain that all connectors are fully seated and the connector locks are fully engaged.
7. Reconnect all related component harness connectors. Be certain that all connectors are fully seated and the connector locks are fully engaged.
8. With the scan tool, erase DTCs.
9. Using the recorded Freeze Frame and Environmental Data, along with the When Monitored and Set Conditions above, operate the vehicle in the conditions that set the DTC.
10. With the scan tool, read PCM DTCs.
Did the DTC return?
Yes
• Replace the Powertrain Control Module (PCM) in accordance with the Service Information. (Refer to 08 - Electrical/8E - Electronic Control Modules/MODULE, Powertrain Control/Removal) .
• Perform the PCM VERIFICATION TEST. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).
No
• Test complete.
• Perform the PCM VERIFICATION TEST. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain
Control (PCM) - Standard Procedure).