DTC P0407:00 [PCM (SKYACTIV-D)]

System malfunction location	LP-EGR control valve position sensor circuit low input
Detection condition	• If the PCM detects the LP-EGR control valve position sensor voltage at the PCM terminal 1AV is less than 0.25 V for 2 s with the following condition met, the PCM determines that the LP-EGR control valve position sensor circuit voltage is low. ― Battery voltage: 8 V or more ― 0.5 s have elapsed after the ignition was switched ON (engine off or on) ― The following DTCs are not detected: • P0652:00, P0653:00
Fail-safe	• PCM restricts engine torque. • Inhibits the DENOx/DESOx control. • Inhibits the diesel particulate filter regeneration control. • Inhibits the EGR control.
Possible cause	• LP-EGR control valve/LP-EGR control valve position sensor connector or terminals malfunction • Short to ground in any of the following LP-EGR control valve position sensor circuits. ― Signal circuit ― Power supply circuit • PCM connector or terminals malfunction • LP-EGR control valve position sensor ground circuit and signal circuit are shorted to each other • Open circuit in LP-EGR control valve position sensor power supply circuit • LP-EGR control valve position sensor malfunction • PCM malfunction

System malfunction location

LP-EGR control valve position sensor circuit low input

Detection condition

• If the PCM detects the LP-EGR control valve position sensor voltage at the PCM terminal 1AV is less than 0.25 V for 2 s with the following condition met, the PCM determines that the LP-EGR control valve position sensor circuit voltage is low.

― Battery voltage: 8 V or more

― 0.5 s have elapsed after the ignition was switched ON (engine off or on)

― The following DTCs are not detected:

• P0652:00, P0653:00

Fail-safe

• PCM restricts engine torque.

• Inhibits the DENOx/DESOx control.

• Inhibits the diesel particulate filter regeneration control.

• Inhibits the EGR control.

Possible cause

• LP-EGR control valve/LP-EGR control valve position sensor connector or terminals malfunction

• Short to ground in any of the following LP-EGR control valve position sensor circuits.

― Signal circuit

― Power supply circuit

• PCM connector or terminals malfunction

• LP-EGR control valve position sensor ground circuit and signal circuit are shorted to each other

• Open circuit in LP-EGR control valve position sensor power supply circuit

• LP-EGR control valve position sensor malfunction

• PCM malfunction

Step	Inspection	Results	Action
1	RECORD VEHICLE STATUS WHEN DTC WAS DETECTED TO UTILIZE WITH REPEATABILITY VERIFICATION • Record the freeze frame data/snapshot data. Note • Recording can be facilitated using the screen capture function of the PC.	—	Go to the next step.
2	VERIFY RELATED REPAIR INFORMATION OR SERVICE INFORMATION AVAILABILITY • Verify related Service Bulletins, on-line repair information, or Service Information availability. • Is any related Information available?	Yes	Perform repair or diagnosis according to the available information. • If the vehicle is not repaired, go to the next step.
No	Go to the next step.
3	INSPECT LP-EGR CONTROL VALVE/LP-EGR CONTROL VALVE POSITION SENSOR CONNECTOR FOR MALFUNCTION • Inspect the applicable connector and terminal. (See CONNECTOR INSPECTION.) • Are the connector and terminal normal?	Yes	Go to the next step.
No	Repair or replace the malfunctioning location and perform the repair completion verification.
4	INSPECT PCM CONNECTOR FOR MALFUNCTION • Inspect the applicable connector and terminal. (See CONNECTOR INSPECTION.) • Are the connector and terminal normal?	Yes	Go to the next step.
No	Repair or replace the malfunctioning location and perform the repair completion verification.
5	INSPECT LP-EGR CONTROL VALVE POSITION SENSOR POWER SUPPLY CIRCUIT AND SIGNAL CIRCUIT AND GROUND CIRCUIT FOR SHORT TO POWER SUPPLY • Inspect the applicable circuit for a short to power supply. (See CIRCUIT INSPECTION.) • Is the circuit normal?	Yes	Go to the next step.
No	Repair or replace the malfunctioning location and perform the repair completion verification.
6	INSPECT LP-EGR CONTROL VALVE POSITION SENSOR POWER SUPPLY CIRCUIT AND SIGNAL CIRCUIT FOR SHORT CIRCUIT • Inspect the applicable circuits for a short circuit. (See CIRCUIT INSPECTION.) • Is the circuit normal?	Yes	Go to repair completion verification.
No	Repair or replace the malfunctioning location and perform the repair completion verification.
7	INSPECT LP-EGR CONTROL VALVE POSITION SENSOR SIGNAL CIRCUIT AND GROUND CIRCUIT FOR OPEN CIRCUIT • Inspect the applicable circuit for open circuit. (See CIRCUIT INSPECTION.) • Is the circuit normal?	Yes	Go to the next step.
No	Repair or replace the malfunctioning location and perform the repair completion verification.
8	INSPECT LP-EGR CONTROL VALVE POSITION SENSOR FOR MALFUNCTION • Inspect the applicable part. (See LP-EGR CONTROL VALVE INSPECTION [SKYACTIV-D 1.8].) • Is the part normal?	Yes	Go to the next step.
No	Repair or replace the malfunctioning location and perform the repair completion verification. (See LP-EGR CONTROL VALVE REMOVAL/INSTALLATION [SKYACTIV-D 1.8].)
Repair completion verification 1	VERIFY THAT VEHICLE IS REPAIRED • Install/connect the part removed/disconnected during the troubleshooting procedure. • Clear the DTC recorded in the memory. (See CLEARING DTC.) • Replicate the vehicle conditions at the time the DTC was detected using the following procedure. ― Perform the KOEO or KOER self test. (See DTC INSPECTION.) • Perform the DTC inspection for the PCM. (See DTC INSPECTION.) • Is the same Pending DTC present?	Yes	Refer to the controller area network (CAN) malfunction diagnosis flow to inspect for a CAN communication error. (See CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW [(E)].) If the CAN communication is normal, perform the diagnosis from Step 1. • If the malfunction recurs, replace the PCM, then go to the next step. (See PCM REMOVAL/INSTALLATION [SKYACTIV-D 1.8].)
No	Go to the next step.
Repair completion verification 2	VERIFY IF OTHER DTCs DISPLAYED • Perform the DTC inspection. (See DTC INSPECTION.) • Are any other DTCs displayed?	Yes	Repair the malfunctioning location according to the applicable DTC troubleshooting.
No	DTC troubleshooting completed.

Step

Inspection

Results

Action

RECORD VEHICLE STATUS WHEN DTC WAS DETECTED TO UTILIZE WITH REPEATABILITY VERIFICATION

• Record the freeze frame data/snapshot data.

Note

• Recording can be facilitated using the screen capture function of the PC.

—

Go to the next step.

VERIFY RELATED REPAIR INFORMATION OR SERVICE INFORMATION AVAILABILITY

• Verify related Service Bulletins, on-line repair information, or Service Information availability.

• Is any related Information available?

Yes

Perform repair or diagnosis according to the available information.

• If the vehicle is not repaired, go to the next step.

Go to the next step.

INSPECT LP-EGR CONTROL VALVE/LP-EGR CONTROL VALVE POSITION SENSOR CONNECTOR FOR MALFUNCTION

• Inspect the applicable connector and terminal.

(See CONNECTOR INSPECTION.)

• Are the connector and terminal normal?

Yes

Go to the next step.

Repair or replace the malfunctioning location and perform the repair completion verification.

INSPECT PCM CONNECTOR FOR MALFUNCTION

• Inspect the applicable connector and terminal.

(See CONNECTOR INSPECTION.)

• Are the connector and terminal normal?

Yes

Go to the next step.

Repair or replace the malfunctioning location and perform the repair completion verification.

INSPECT LP-EGR CONTROL VALVE POSITION SENSOR POWER SUPPLY CIRCUIT AND SIGNAL CIRCUIT AND GROUND CIRCUIT FOR SHORT TO POWER SUPPLY

• Inspect the applicable circuit for a short to power supply.

(See CIRCUIT INSPECTION.)

• Is the circuit normal?

Yes

Go to the next step.

Repair or replace the malfunctioning location and perform the repair completion verification.

INSPECT LP-EGR CONTROL VALVE POSITION SENSOR POWER SUPPLY CIRCUIT AND SIGNAL CIRCUIT FOR SHORT CIRCUIT

• Inspect the applicable circuits for a short circuit.

(See CIRCUIT INSPECTION.)

• Is the circuit normal?

Yes

Go to repair completion verification.

Repair or replace the malfunctioning location and perform the repair completion verification.

INSPECT LP-EGR CONTROL VALVE POSITION SENSOR SIGNAL CIRCUIT AND GROUND CIRCUIT FOR OPEN CIRCUIT

• Inspect the applicable circuit for open circuit.

(See CIRCUIT INSPECTION.)

• Is the circuit normal?

Yes

Go to the next step.

Repair or replace the malfunctioning location and perform the repair completion verification.

INSPECT LP-EGR CONTROL VALVE POSITION SENSOR FOR MALFUNCTION

• Inspect the applicable part.

(See LP-EGR CONTROL VALVE INSPECTION [SKYACTIV-D 1.8].)

• Is the part normal?

Yes

Go to the next step.

Repair or replace the malfunctioning location and perform the repair completion verification.

(See LP-EGR CONTROL VALVE REMOVAL/INSTALLATION [SKYACTIV-D 1.8].)

Repair completion verification 1

VERIFY THAT VEHICLE IS REPAIRED

• Install/connect the part removed/disconnected during the troubleshooting procedure.

• Clear the DTC recorded in the memory.

(See CLEARING DTC.)

• Replicate the vehicle conditions at the time the DTC was detected using the following procedure.

― Perform the KOEO or KOER self test.

(See DTC INSPECTION.)

• Perform the DTC inspection for the PCM.

(See DTC INSPECTION.)

• Is the same Pending DTC present?

Yes

Refer to the controller area network (CAN) malfunction diagnosis flow to inspect for a CAN communication error.

(See CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW [(E)].)

If the CAN communication is normal, perform the diagnosis from Step 1.

• If the malfunction recurs, replace the PCM, then go to the next step.

(See PCM REMOVAL/INSTALLATION [SKYACTIV-D 1.8].)

Go to the next step.

Repair completion verification 2

VERIFY IF OTHER DTCs DISPLAYED

• Perform the DTC inspection.

(See DTC INSPECTION.)

• Are any other DTCs displayed?

Yes

Repair the malfunctioning location according to the applicable DTC troubleshooting.

DTC troubleshooting completed.

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