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 DTC P0406 [MZR-CD (RF Turbo)]

DTC P0406 [MZR-CD (RF Turbo)]

id0102f1820700

DTC P0406

EGR valve position sensor circuit high input

DETECTION CONDITION

• The PCM monitors input voltage from EGR position sensor when the engine switch is ON position. If input voltage is more than 4.9 V, the PCM determines that the EGR valve position sensor circuit has a malfunction.
Diagnostic support note
• MIL illuminates if PCM detects the above malfunctioning condition in two consecutive drive cycles or in one drive cycle while the DTC for the same malfunction has been stored in the PCM.
• PENDING CODE is available if PCM detects the above malfunction conditions during first drive cycle.
• FREEZE FRAME DATA is available.
• DTC is stored in the PCM memory.

POSSIBLE CAUSE

• EGR valve position sensor malfunction
• Connector or terminal malfunction
• Open circuit between EGR valve terminal C and PCM terminal 70
• Short to constant voltage supply between EGR valve terminal E and PCM terminal 53

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
IDENTIFY TRIGGER DTC FOR FREEZE FRAME DATA
• Is DTC P0406 on FREEZE FRAME DATA?
Yes
Go to the next step.
No
Go to troubleshooting procedures for DTC in FREEZE FRAME DATA.
4
INSPECT EGR VALVE CONNECTOR
• Turn the engine switch to off.
• Verify that the EGR valve 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 CONNECTOR FOR POOR CONNECTION
• Disconnect the EGR valve 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, then go to Step 11.
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 terminal E (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 terminal C and PCM terminal 70.
• 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 wiring harness side connector between terminal A and E.
• 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
• Make sure to reconnect all disconnected connectors.
• Turn the engine switch to the ON position (engine off).
• Clear the DTC from the PCM memory using the WDS or equivalent.
• Start the engine.
• Is the same DTC present?
Yes
Replace the PCM, then go to the next step.
No
Go to the next step.
12
VERIFY AFTER REPAIR PROCEDURE
• Perform "AFTER REPAIR PROCEDURE".
• Is any DTCs present?
Yes
Go to the applicable DTC inspection.
No
Troubleshooting completed.