DTC P0403 [AJ] (VIN: JM0 LW10J300 301406-, JMZ LW69J7*# 307683-, JM8 LW28J**# 301514-, JM8 LW28A**# 301514- (Assumed))

BME010200400W06

DTC P0403

EGR valve (stepper motor) circuit malfunction

DETECTION CONDITION

• The PCM monitors the input voltages from EGR valve control signals. If voltage at PCM terminals 99, 98, 72 and/or 73 remain low or high, PCM determines that the EGR valve circuit has malfunctioned.
Diagnostic support note
• This is a continuous monitor. (CCM)
• The MIL illuminates if the PCM detects the above malfunction 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 the PCM detects the above malfunction condition during the first drive cycle.
• FREEZE FRAME DATA is available.
• DTC is stored in the PCM memory.

POSSIBLE CAUSE

• EGR valve malfunction
• Connector or terminal malfunction
• Short to power supply in wiring harness between EGR valve terminal E and PCM terminal 98
• Short to power supply in wiring harness between EGR valve terminal A and PCM terminal 99
• Short to power supply in wiring harness between EGR valve terminal B and PCM terminal 72
• Short to power supply in wiring harness between EGR valve terminal F and PCM terminal 73
• Short to ground circuit in wiring between EGR valve terminal E and PCM terminal 98
• Short to ground circuit in wiring between EGR valve terminal A and PCM terminal 99
• Short to ground circuit in wiring between EGR valve terminal B and PCM terminal 72
• Short to ground circuit in wiring between EGR valve terminal F and PCM terminal 73
• Open circuit in wiring between EGR valve terminal E and PCM terminal 98
• Open circuit in wiring between EGR valve terminal A and PCM terminal 99
• Open circuit in wiring between EGR valve terminal B and PCM terminal 72
• Open circuit in wiring between EGR valve terminal F and PCM terminal 73
• Open circuit in wiring between main relay terminal D and EGR valve terminal C
• Open circuit in wiring between main relay terminal D and EGR valve terminal D
• PCM malfunction

Diagnostic procedure

STEP

INSPECTION

ACTION

1
VERIFY RELATED REPAIR INFORMATION AVAILABILITY
• Check for related Service Information and/or on-line repair information availability.
• Is any 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.
2
CLASSIFY INTERMITTENT CONCERN OR CONTINUOUS CONCERN
• Turn the ignition switch off, then to the ON position (Engine off).
• Is same DTC present?
Yes
Go to the next step.
No
Refer to intermittent concern.
3
INSPECT POOR CONNECTION OF EGR VALVE
• Turn the ignition switch off.
• Disconnect EGR valve connector.
• Check for poor connection (damaged, pulled-out terminals, corrosion, etc.).
• Is there any malfunction?
Yes
Repair or replace terminals and/or connector, then go to Step 8.
No
Go to the next step.
4
INSPECT POWER CIRCUIT FOR OPEN CIRCUIT
• Turn the ignition switch to the ON position (Engine off).
• Measure following EGR valve power circuit terminal voltage.
- EGR valve terminal C and body ground
- EGR valve terminal D and body ground
•  Is voltage B+?
Yes
Go to the next step.
No
Repair or replace harness for open circuit then go to Step 8.
5
INSPECT EGR VALVE
• Inspect the EGR valve.
• Is the EGR valve normal?
Yes
Go to the next step.
No
Replace EGR valve, then go to Step 8.
6
INSPECT FOR CONTROL CIRCUIT FOR SHORT TO GROUND
• Check continuity following EGR valve control circuit.
- EGR valve terminal E and body ground
- EGR valve terminal A and body ground
- EGR valve terminal B and body ground
- EGR valve terminal F and body ground
• Is there continuity?
Yes
Repair or replace harness for short to ground, then go to Step 8.
No
Go to the next step.
7
INSPECT CONTROL CIRCUIT FOR OPEN CIRCUIT
•  Connect the PCM connector.
• Check continuity following EGR control circuit.
- EGR valve terminal E and PCM terminal 98
- EGR valve terminal A and PCM terminal 99
- EGR valve terminal B and PCM terminal 72
- EGR valve terminal F and PCM terminal 73
• Is there continuity?
Yes
Go to the next step.
No
Repair or replace harness for open circuit then go to the next step
8
VERIFY TROUBLESHOOTING OF DTC P0403 COMPLETED
• Make sure to reconnect all disconnected connectors.
• Turn the ignition switch off, then to the ON position (Engine off).
• Is same DTC present?
Yes
Replace PCM, then go to the next step.
No
Go to the next step.
9
VERIFY AFTER REPAIR PROCEDURE
• Perform the "After Repair Procedure".
• Are any DTCs present?
Yes
Go to the applicable DTC inspection.
No
Troubleshooting completed.