DTC P0403 [MZ-CD 1.6 (Y6)]


id0102c3807100

DTC P0403

EGR valve actuator circuit malfunction

DETECTION CONDITION
•  The PCM monitors the input voltage from the EGR valve actuator signal. If the voltages at PCM deviates from the threshold, the PCM determines that the there is an EGR valve actuator circuit problem.
POSSIBLE CAUSE
•  EGR valve actuator malfunction
•  Connector or terminal malfunction
•  Open circuit in wiring harness between EGR valve actuator terminal C and PCM terminal 227
•  Open circuit in wiring harness between EGR valve actuator terminal D and PCM terminal 228
•  Short to ground in wiring harness between EGR valve actuator terminal C and PCM terminal 227
•  Short to ground in wiring harness between EGR valve actuator terminal D and PCM terminal 228
•  Short to power supply in wiring harness between EGR valve actuator terminal C and PCM terminal 227
•  Short to power supply in wiring harness between EGR valve actuator terminal D and PCM terminal 228
•  PCM malfunction

Diagnostic procedure

STEP

INSPECTION

ACTION

1
VERIFY FREEZE FRAME DATA HAS BEEN RECORDED
•  Has the 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
•  Verify related service repair information availability.
•  Is any related repair information available?
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”.
4
INSPECT EGR VALVE ACTUATOR CONNECTOR FOR POOR CONNECTION
•  Turn the engine switch off.
•  Disconnect the EGR valve actuator connector.
•  Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
•  Is there any malfunction?
Yes
Repair or replace the terminal, then go to Step 10.
No
Go to the next step.
5
INSPECT EGR VALVE ACTUATOR CONTROL CIRCUIT FOR SHORT TO POWER SUPPLY
•  Turn the engine switch to the ON position (Engine off).
•  Measure the voltage between the following terminals:
―  EGR valve actuator terminal C (wiring harness-side) and body ground.
―  EGR valve actuator terminal D (wiring harness-side) and body ground.
•  Is the voltage B+?
Yes
Go to the next step.
No
Repair or replace the wiring harness for a possible open circuit or short to ground, then go to Step 10.
6
INSPECT EGR VALVE ACTUATOR
•  Inspect the EGR valve actuator.
•  Is there any malfunction?
Yes
Replace the EGR valve actuator, then go to Step 10.
No
Go to the next step.
7
INSPECT PCM CONNECTOR FOR POOR CONNECTION
•  Turn the engine switch off.
•  Disconnect the PCM connector.
•  Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
•  Is there any malfunction?
Yes
Repair or replace the terminal, then go to Step 10.
No
Go to the next step.
8
INSPECT EGR VALVE ACTUATOR CONTROL CIRCUIT FOR SHORT TO GROUND
•  Turn the engine switch off.
•  Inspect for continuity between the following terminals:
―  EGR valve actuator terminal C (wiring harness-side) and body ground
―  EGR valve actuator terminal D (wiring harness-side) and body ground
•  Is there continuity?
Yes
Repair or replace the wiring harness for a possible short to ground, then go to Step 10.
No
Go to the next step.
9
INSPECT EGR VALVE ACTUATOR CONTROL CIRCUIT FOR OPEN CIRCUIT
•  Turn the engine switch off.
•  Inspect for continuity between the following terminals:
―  EGR valve actuator terminal C (wiring harness-side) and PCM terminal 227 (wiring harness-side)
―  EGR valve actuator terminal D (wiring harness-side) and PCM terminal 228 (wiring harness-side)
•  Is there continuity?
Yes
Go to the next step.
No
Repair or replace the wiring harness for a possible open circuit, then go to the next step.
10
VERIFY THAT DTC P0403 TROUBLESHOOTING IS COMPLETED
•  Make sure to reconnect all disconnected connectors.
•  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
Replace the PCM, then go to the next step.
No
Go to the next step.
11
VERIFY AFTER REPAIR PROCEDURE
•  Perform the after repair procedure.
•  Are any DTCs present?
Yes
Go to the applicable DTC inspection.
No
DTC troubleshooting completed.