DTC P0405 or P0406
Diagnostic Instructions
DTC Descriptors
| DTC P0405 00: Exhaust Gas Recirculation (EGR)
Position Sensor Circuit Low Voltage |
| DTC P0406 00: Exhaust Gas Recirculation (EGR)
Position Sensor Circuit High Voltage |
Diagnostic Fault Information
Circuit
|
Short to Ground
|
Open/High Resistance
|
Short to Voltage
|
Signal Performance
|
5V Reference
|
P0405 00
|
P0405 00
|
P0406 00
|
—
|
Signal
|
P0405 00
|
P0405 00
|
P0406 00
|
—
|
Low Reference
|
—
|
P0406 00
|
—
|
—
|
|
| |
Typical Scan Tool Data
EGR Position Sensor
Circuit
|
Short to Ground
|
Open
|
Short to Voltage
|
Operating Conditions: engine running
Parameter Normal Range: 0.98–4.98
V
|
5V Reference
|
0 V
|
0 V
|
4.98 V
|
Signal
|
0 V
|
0 V
|
4.98 V
|
Low Reference
|
—
|
4.8 V
|
—
|
|
| |
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 V
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
| • |
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 V for more than 1
s.
P0406
The EGR position sensor voltage is more than 4.75 V for more than 3
s.
Action Taken When the DTC Sets
DTC P0405 and P0406 are Type B DTCs.
Conditions for Clearing the DTC
DTC P0405 and P0406 are Type B DTCs.
Reference Information
Schematic Reference
Engine Controls Schematics
Connector End View Reference
Component Connector End Views
Description and Operation
Exhaust Gas Recirculation (EGR) System Description
Electrical Information Reference
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Verification
| 1. |
Ignition ON, observe the scan
tool EGR Position Sensor parameter. The reading should be between
0.25–4.75 V. |
| 2. |
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 Q14 Exhaust Gas Recirculation
Valve. |
| 2. |
Ignition OFF, test for less
than 5 Ω between the low reference circuit terminal 3 and
ground. |
| ⇒ |
If greater than the specified range, test the low
reference circuit for an open/high resistance. If the circuit tests
normal, replace the K20 Engine Control Module. |
| 3. |
Ignition ON, test for
4.8–5.2 V between the 5 V reference circuit terminal 1 and
ground. |
| ⇒ |
If less than the specified range, test the 5 V
reference circuit for a short to ground or an open/high resistance.
If the circuit tests normal, replace the K20 Engine Control
Module. |
| ⇒ |
If greater than the specified range, test the 5 V
reference circuit for a short to voltage. If the circuit tests
normal, replace the K20 Engine Control Module. |
| 4. |
Verify the scan tool EGR
Position Sensor parameter is less than 0.3 V. |
| ⇒ |
If greater than the specified range, test the
signal circuit terminal 5 for a short to voltage. If the circuit
tests normal, replace the K20 Engine Control Module. |
| 5. |
Install a 3 A fused jumper
wire between the signal circuit terminal 5 and the 5 V reference
circuit terminal 1. Verify the scan tool EGR Position Sensor
parameter is greater than 4.8 V. |
| ⇒ |
If less than the specified range, test the signal
circuit for short to ground or an open/high resistance. If the
circuit tests normal, replace the K20 Engine Control Module. |
| 6. |
If all circuits test normal,
test or replace the Q14 Exhaust Gas Recirculation Valve.
|
Repair Instructions
Perform the
Diagnostic Repair Verification after completing the diagnostic
procedure.
|
