Diagnostic Instructions

DTC Descriptors

DTC P02E8: Diesel Intake Air (IA) Flow Position Sensor Circuit Low Voltage

DTC P02E9: Diesel Intake Air (IA) Flow Position Sensor Circuit High Voltage

Diagnostic Fault Information

Circuit	Short to Ground	High Resistance	Open	Short to Voltage
IA Flow Valve 5-Volt Reference Voltage	P0642	P02E9	P02E8	P0336, P0643
IA Flow Valve Sensor Signal	P02E8	P02E7	P02E8	P02E9
IA Flow Valve Low Reference	--	P02E7	P02E9	--
IA Flow Valve Motor Control 1	P02E0	--	P02E0	P02E0
IA Flow Valve Motor Control 2	P02E0	--	P02E0	P02E0

Circuit/System Description

The intake air (IA) valve is a normally open valve and is only operated during a DPF regeneration. The position of the IA valve is controlled by the engine control module (ECM). The IAF Valve system uses a position sensor located within the valve assembly to monitor the position of the valve. The position sensor has the following circuits:

The IAF valve uses a motor to move the valve to a closed position and spring tension returns it to the open position. The motor has the following circuits:

Conditions for Running the DTC

P02E8 and P02E9

Conditions for Setting the DTC

P02E8

The IAF valve position is less than 0.102 volt for 3 seconds.

P02E9

The IAF valve position is greater than 4.75 volts for 3 seconds.

Action Taken When the DTC Sets

Conditions for Clearing the DTC

DTCs P02E8 and P02E9 are Type B DTCs.

Reference Information

Schematic Reference

Engine Controls Schematics

Connector End View Reference

Electrical Information Reference

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Circuit/System Verification

1. Command the IA valve from 100 percent to 0 percent. The IAF Valve Commanded Position and the IAF Valve Position parameter should match.
2. After the engine has been running, turn OFF the ignition. Observe the IA Valve Position parameter fluctuates between 100 percent and 0 percent several times.
3. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the IA valve. Allow up to 2 minutes for the ECM to completely power down.
2. Ignition OFF, test for less than 5 ohms of resistance between the low reference circuit terminal C and ground.

⇒	If greater than 5 ohms, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the ECM.

3. Ignition ON, test for 4.8-5.2 volts between 5-volt reference circuit terminal F and ground.

⇒	If less than 4.8 volts, test 5-volt reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the ECM.

⇒	If greater than 5.2 volts, test the 5-volt reference circuit for a short to voltage. If the circuit tests normal, replace the ECM.

4. Verify the scan tool IAF valve position sensor voltage is less than 0.1 volt.

⇒	If greater than 0.1 volt, test the signal circuit terminal E for a short to voltage. If the circuit tests normal, replace the ECM.

5. Install a 3A fused jumper wire between the signal circuit terminal E and the 5-volt reference circuit terminal F of the IA valve harness connector. Verify that the voltage is more than 4.8 volt.

⇒	If less than 4.8 volt, test the IA valve signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the ECM.

6. If all circuits test normal, replace the IA valve.

Repair Instructions

Repair Verification

1. Install any components or connectors that have been removed or replaced during diagnosis.
2. Perform any adjustment, programming, or setup procedures that are required when a component or module is removed or replaced.
3. Clear the DTCs.
4. Turn OFF the ignition for 90 seconds.
5. Duplicate the Conditions for Running the DTC and use the Freeze Frame/Failure Records, if applicable, in order to verify the DTC does not reset. If the DTC resets or another DTC is present, refer to the Diagnostic Trouble Code (DTC) List - Vehicle and perform the appropriate diagnostic procedure.
6. Perform the Diesel Particulate Filter (DPF) Service Regeneration.