DTC P0406 [WL-C, WE-C (Thailand, General (L.H.D. R.H.D.) specs.)]

id0102b0820700

DTC P0406

EGR valve position sensor circuit high input
DETECTION CONDITION
•  The PCM monitors the input voltage from the EGR valve position sensor while the engine is running. If the input voltage is more than 4.9 V, the PCM determines that the EGR valve position sensor circuit has a malfunction.
POSSIBLE CAUSE
•  EGR valve position sensor malfunction
•  Connector or terminal malfunction
•  Open circuit between EGR valve position sensor terminal A and PCM terminal 110
•  Short to constant voltage supply between EGR valve position sensor terminal C and PCM terminal 116

Diagnostic procedure

STEP

INSPECTION

ACTION
1
VERIFY FREEZE FRAME DATA HAS BEEN RECORDED
•  Has FREEZE FRAME DATA been recorded?
Yes
Go to the next step.
No
Record the FREEZE FRAME DATA on the repair order, then go to the next step.
2
VERIFY RELATED REPAIR INFORMATION AVAILABILITY
•  Check for related service repair information availability?
Yes
Perform repair or diagnosis according to the available repair information.
•  If the vehicle is not repaired, go to the next step.
No
Go to the next step.
3
VERIFY CURRENT SIGNAL STATUS: IS CONCERN INTERMITTENT OR CONSTANT?
•  Connect the M-MDS to the DLC-2.
•  Clear the DTC from the PCM memory using the M-MDS.
•  Run the vehicle under the FREEZE FRAME DATA stored condition.
•  Is the same DTC present?
Yes
Go to the next step.
No
Intermittent concern exists.
Perform the “INTERMITTENT CONCERNS TROUBLESHOOTING”.
(See INTERMITTENT CONCERN TROUBLESHOOTING [WL-C, WE-C].)
4
INSPECT EGR VALVE POSITION SENSOR CONNECTOR
•  Turn the engine switch to off.
•  Verify that the EGR valve position sensor connector is connected securely.
•  Is connector normal?
Yes
Go to the next step.
No
Connect the connector securely, then go to Step 11.
5
INSPECT EGR VALVE POSITION SENSOR CONNECTOR FOR POOR CONNECTION
•  Disconnect the EGR valve position sensor connector.
•  Inspect for poor connection (such as damaged, pulled-out terminals, corrosion).
•  Is there any malfunction?
Yes
Repair or replace suspected terminal, then go to Step 11.
No
Go to the next step.
6
INSPECT EGR VALVE POSITION SENSOR
•  Perform EGR valve position sensor inspection.
•  Is the EGR valve position sensor normal?
Yes
Go to the next step.
No
Replace the EGR valve position sensor, then go to Step 11.
(See EGR SYSTEM REMOVAL/INSTALLATION [WL-C, WE-C].)
7
INSPECT EGR VALVE POSITION SENSOR SIGNAL FOR SHORT TO POWER SUPPLY
•  Turn the engine switch to ON (engine off).
•  Measure voltage between EGR valve position terminal C (wiring harness-side) and body ground.
•  Is voltage more than 4.9V?
Yes
Repair or replace for short to power supply, then go to Step 11.
No
Go to the next step.
8
VERIFY EGR VALVE POSITION SENSOR GROUND CIRCUIT FOR OPEN CIRCUIT
•  inspect for continuity at wiring harness-side connector between EGR valve position sensor terminal A and PCM terminal 110.
•  Is there any continuity?
Yes
Go to the next step.
No
Repair or replace for open circuit.
Then go to Step 11.
9
INSPECT PCM CONNECTORS FOR POOR CONNECTION
•  Turn the engine switch off.
•  Disconnect the PCM connector.
•  Inspect for poor connection (such as damaged/pulled-out pins, and corrosion).
•  Is there any malfunction?
Yes
Repair or replace terminal, then go to Step 11.
No
Go to the next step.
10
VERIFY EGR POSITION SIGNAL CIRCUIT FOR SHORT TO CONSTANT VOLTAGE CIRCUIT
•  inspect for continuity at EGR valve position sensor wiring harness side connector between terminal B and C.
•  Is there continuity?
Yes
Repair or replace for short circuit, then go to the next step.
No
Go to the next step.
11
VERIFY TROUBLESHOOTING OF DTC P0406 COMPLETED
•  Turn the engine switch off.
•  Make sure to reconnect all disconnected connectors.
•  Turn the engine switch to the ON position (Engine off).
•  Clear the DTC from the memory using the M-MDS.
•  Run the vehicle under the FREEZE FRAME DATA stored condition.
•  Is the same DTC present?
Yes
Replace the PCM, then go to the next step.
(See PCM REMOVAL/INSTALLATION [WL-C, WE-C].)
No
Go to the next step.
12
VERIFY AFTER REPAIR PROCEDURE
•  Perform the “After Repair Procedure“.
•  Are any DTCs present?
Yes
Go to the applicable DTC inspection.
(See DTC TABLE [WL-C, WE-C (Thailand, General (L.H.D. R.H.D.) specs.)].)
No
Troubleshooting completed.