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DTC P1378:00 [PCM (SKYACTIV-D)]

id0102t5149300

Outline

System malfunction location

Fuel injector circuit low input

Detection condition

•  The PCM detected that the voltage output from the boost circuit for the fuel injector control built into the PCM is less than 120 V when all of the following conditions are met.

―  Battery positive voltage: 8.0 V or more

Fail-safe

•  PCM restricts engine torque.

•  Limits the maximum engine speed.

•  Inhibits the DENOx/DESOx control.

•  Inhibits the diesel particulate filter regeneration control.

•  Inhibits the EGR control.

•  PCM restricts engine-transaxle integration control. (ATX)

•  Inhibits engine-stop by operating the i-stop function.

Possible cause

•  PCM malfunction

System wiring diagram

•  Not applicable

Connector diagram

•  Not applicable

System malfunction location	Fuel injector circuit low input
Detection condition	• The PCM detected that the voltage output from the boost circuit for the fuel injector control built into the PCM is less than 120 V when all of the following conditions are met. ― Battery positive voltage: 8.0 V or more
Fail-safe	• PCM restricts engine torque. • Limits the maximum engine speed. • Inhibits the DENOx/DESOx control. • Inhibits the diesel particulate filter regeneration control. • Inhibits the EGR control. • PCM restricts engine-transaxle integration control. (ATX) • Inhibits engine-stop by operating the i-stop function.
Possible cause	• PCM malfunction
System wiring diagram	• Not applicable
Connector diagram	• Not applicable

Diagnostic Procedure

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 FOR OTHER RELATED DTCs

•  Perform the DTC inspection for the PCM.
(See DTC INSPECTION.)

•  Are any other DTCs displayed?

Yes

Repair the malfunctioning location according to the applicable DTC troubleshooting.

(See DTC TABLE [PCM (SKYACTIV-D)].)

No

Go to the next step.

4

PERFORM DTC INSPECTION AND VERIFY IF MALFUNCTIONING PART IS PCM

•  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 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

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
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.
2		No	Go to the next step.
3	INSPECT FOR OTHER RELATED DTCs • Perform the DTC inspection for the PCM. (See DTC INSPECTION.) • Are any other DTCs displayed?	Yes	Repair the malfunctioning location according to the applicable DTC troubleshooting. (See DTC TABLE [PCM (SKYACTIV-D)].)
3		No	Go to the next step.
4	PERFORM DTC INSPECTION AND VERIFY IF MALFUNCTIONING PART IS PCM • 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 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].)
4		No	Go to the next step.
Repair completion verification	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.
Repair completion verification		No	DTC troubleshooting completed.