Diagnostic Instructions
| • | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
| • | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
| • | Diagnostic Procedure Instructions provide an overview of each diagnostic category. |
DTC Descriptors
DTC P0405 : Exhaust Gas Recirculation (EGR) Position Sensor Circuit Low VoltageDTC P0406: Exhaust Gas Recirculation (EGR) Position Sensor Circuit High Voltage
Diagnostic Fault Information
Circuit | Short to Ground | High Resistance | Open | Short to Voltage | Signal Performance |
|---|---|---|---|---|---|
EGR 5-Volt Reference Voltage | P0107, P0698, P2564 | P0102, P0401, P046C | P0405 | P0106, P0699, P2227, P2565 | -- |
EGR Sensor Signal | P0405 | P0101, P0405 | P0405 | P0699, P0106, P2565, P0401 | -- |
EGR Low Reference | -- | P0401, P046C | P0406 | -- | -- |
EGR MTR High Control | P0403 | P0401, P046C | P0403 | P046C | -- |
EGR MTR Low Control | P0403, P046C | P0401, P046C | P0403 | P0403 | -- |
Typical Scan Tool Data
Circuit | Normal Range | Short to Ground | Open | Short to Voltage |
|---|---|---|---|---|
Operating Conditions: Engine Running, ECT sensor is less than 60°C (140°F) | ||||
EGR 5-Volt Reference Voltage | 0.98 Volts | 0 Volts | 0 Volts | 1.29 Volts |
EGR Sensor Signal | 0.98 Volts | 0 Volts | 0 Volts | 4.98 Volts |
EGR Low Reference | 0.98 Volts | -- | 4.8 Volts | -- |
Circuit/System Description
The engine control module (ECM) uses the exhaust gas recirculation (EGR) position sensor to determine the position of the EGR valve. The ECM sends a reference voltage through the 5-volt reference circuit to the EGR position sensor. The ECM provides a voltage return path for the sensor through the low reference circuit. A variable voltage signal, based on the EGR valve position, is sent from the sensor to the ECM through the EGR position sensor signal circuit. If the ECM detects an EGR position sensor voltage that is less than or more than the normal operating range, DTC P0405 or P0406 sets.
Conditions for Running the DTC
| • | DTCs P0698 and P0699 are not set. |
| • | The ignition is ON. |
| • | This DTC runs continuously when the above conditions are met. |
Conditions for Setting the DTC
P0405
The EGR position sensor voltage is less than 0.26 volt for more than 3 seconds.
P0406
The EGR position sensor voltage is more than 4.75 volt for more than 3 seconds.
Action Taken When the DTC Sets
| • | DTCs P0405 and P0406 are Type B DTCs. |
| • | Diesel particulate filter (DPF) regeneration is inhibited. |
Conditions for Clearing the DTC
DTCs P0405 and P0406 are Type B DTCs.
Reference Information
Schematic Reference
Connector End View Reference
Electrical Information Reference
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Circuit/System Verification
- The EGR Position Sensor parameter is between 0.25-4.75 volts.
- 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
- Ignition OFF, test for less than 1 ohm of resistance between the low reference circuit terminal B and ground.
- Ignition ON, test for 4.8-5.2 volts between the 5-volt reference circuit terminal A and ground.
- Ignition ON, and the EGR valve disconnected, observe that the EGR Position parameter on the scan tool is 0 volt.
- Ignition ON and the EGR valve disconnected, connect a jumper wire between the 5-volt reference circuit terminal A of the EGR valve and the signal circuit terminal C of the EGR valve and observe with a scan tool that the EGR sensor parameter displays 4.98-5.02 volts.
- If the circuits, test normal replace the EGR valve motor.
| ⇒ | If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the ECM. |
| ⇒ | If less than the specified range, test the 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 the specified range, test the 5-volt reference circuit for a short to voltage. If the circuit tests normal, replace the ECM. |
| ⇒ | If the EGR Position parameter is more than 0 volt, test the signal circuit for a short to voltage. If the circuits test normal, replace the ECM. |
| ⇒ | If the EGR Sensor parameter is less than 4.98 volts, test the signal circuit for an open, short to ground, or high resistance. If the circuits test normal, replace the control module. |
Repair Instructions
| • | Control Module References for ECM replacement, setup, and programming. |
Repair Verification
- Install any components or connectors that have been removed or replaced during diagnosis.
- Perform any adjustment, programming, or setup procedures that are required when a component or module is removed or replaced.
- Clear the DTCs.
- Turn OFF the ignition for 90 seconds.
- 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.
- Perform the Diesel Particulate Filter (DPF) Service Regeneration.
