DTC P0403 [MZ-CD 1.6 (Y6)]


B3E010200400W14

DTC P0403

EGR valve actuator circuit malfunction

DETECTION CONDITION

• Short to power supply or Ground, or experiencing excess temperature (individual error identification not possible)

POSSIBLE CAUSE

• EGR valve actuator malfunction
• Connector or terminal malfunction
• Open circuit in wiring harness between EGR valve actuator terminal D and PCM terminal 227
• Open circuit in wiring harness between EGR valve actuator terminal C and PCM terminal 228
• Short to ground in wiring harness between EGR valve actuator terminal D and PCM terminal 227
• Short to ground in wiring harness between EGR valve actuator terminal C and PCM terminal 228
• Short to power supply in wiring harness between EGR valve actuator terminal D and PCM terminal 227
• Short to power supply in wiring harness between EGR valve actuator terminal C and PCM terminal 228
• PCM malfunction

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
• 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 WDS or equivalent to the DLC-2.
• Clear the DTC from the PCM memory using the WDS or equivalent.
• 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 D (wiring harness-side) and PCM terminal 227 (wiring harness-side)
- EGR valve actuator terminal C (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 TROUBLESHOOTING OF DTC P0403 COMPLETED
• Make sure to reconnect all disconnected connectors.
• Clear the DTC from the PCM memory using the WDS or equivalent.
• 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.