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DTC P18A4:00 [PCM (SKYACTIV-D)]

id0102t5977200

Outline

System malfunction location

PCM i-ACTIV AWD control system

Detection condition

•  A condition in which the difference between the target current of the AWD solenoid control current and the actual current is the specification or more continues for the specified time or more.

Fail-safe

•  Inhibits the i-ACTIV AWD control.

Possible cause

•  Detects high differential oil temperature to switch to protect the system

•  i-ACTIV AWD system-related part connector or terminal malfunction

•  AWD solenoid malfunction

•  Electrical supply unit (ESU) malfunction

•  PCM malfunction

System wiring diagram

•  Not applicable

Connector diagram

•  Not applicable

System malfunction location	PCM i-ACTIV AWD control system
Detection condition	• A condition in which the difference between the target current of the AWD solenoid control current and the actual current is the specification or more continues for the specified time or more.
Fail-safe	• Inhibits the i-ACTIV AWD control.
Possible cause	• Detects high differential oil temperature to switch to protect the system • i-ACTIV AWD system-related part connector or terminal malfunction • AWD solenoid malfunction • Electrical supply unit (ESU) malfunction • 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

ALLOW THE VEHICLE TO COOL DOWN FOR WHILE

•  Switch the ignition to off and allow vehicle to cool down.

—

Go to the next step.

4

INSPECT i-ACTIV AWD SYSTEM-RELATED PART CONNECTORS FOR MALFUNCTION

•  Inspect the following connectors and terminals.
(See CONNECTOR INSPECTION.)

―  Coupling component temperature sensor

―  Differential oil temperature sensor

―  AWD solenoid

―  Electrical supply unit (ESU)

•  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 AWD SOLENOID FOR MALFUNCTION

•  Inspect the applicable part.
(See AWD SOLENOID INSPECTION.)

•  Is the part normal?

Yes

Go to the next step.

No

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

(See COUPLING COMPONENT REMOVAL/INSTALLATION [(E)].)

6

VERIFY ELECTRICAL SUPPLY UNIT (ESU) DTCs

•  Perform the DTC inspection for the body control module (BCM).
(See DTC INSPECTION.)

•  Are any electrical supply unit (ESU) DTCs displayed?

Yes

Repair the malfunctioning location according to the applicable DTC troubleshooting.

(See DTC TABLE [BODY CONTROL MODULE (BCM) (E)].)

No

Go to the next step.

7

INSPECT ELECTRICAL SUPPLY UNIT (ESU) FOR MALFUNCTION

•  Inspect the following connectors and terminals.
(See ELECTRICAL SUPPLY UNIT (ESU) INSPECTION.)

―  Coupling component temperature sensor

―  Differential oil temperature sensor

―  AWD solenoid

•  Are all the connectors and terminals normal?

Yes

Go to the next step.

No

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

Repair completion verification 1

VERIFY THAT VEHICLE IS REPAIRED

•  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.

―  Switch the ignition ON (engine off)

•  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
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	ALLOW THE VEHICLE TO COOL DOWN FOR WHILE • Switch the ignition to off and allow vehicle to cool down.	—	Go to the next step.
4	INSPECT i-ACTIV AWD SYSTEM-RELATED PART CONNECTORS FOR MALFUNCTION • Inspect the following connectors and terminals. (See CONNECTOR INSPECTION.) ― Coupling component temperature sensor ― Differential oil temperature sensor ― AWD solenoid ― Electrical supply unit (ESU) • Are the connector and terminal normal?	Yes	Go to the next step.
4		No	Repair or replace the malfunctioning location and perform the repair completion verification.
5	INSPECT AWD SOLENOID FOR MALFUNCTION • Inspect the applicable part. (See AWD SOLENOID INSPECTION.) • Is the part normal?	Yes	Go to the next step.
5		No	Repair or replace the malfunctioning location and perform the repair completion verification. (See COUPLING COMPONENT REMOVAL/INSTALLATION [(E)].)
6	VERIFY ELECTRICAL SUPPLY UNIT (ESU) DTCs • Perform the DTC inspection for the body control module (BCM). (See DTC INSPECTION.) • Are any electrical supply unit (ESU) DTCs displayed?	Yes	Repair the malfunctioning location according to the applicable DTC troubleshooting. (See DTC TABLE [BODY CONTROL MODULE (BCM) (E)].)
6		No	Go to the next step.
7	INSPECT ELECTRICAL SUPPLY UNIT (ESU) FOR MALFUNCTION • Inspect the following connectors and terminals. (See ELECTRICAL SUPPLY UNIT (ESU) INSPECTION.) ― Coupling component temperature sensor ― Differential oil temperature sensor ― AWD solenoid • Are all the connectors and terminals normal?	Yes	Go to the next step.
7		No	Repair or replace the malfunctioning location and perform the repair completion verification.
Repair completion verification 1	VERIFY THAT VEHICLE IS REPAIRED • 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. ― Switch the ignition ON (engine off) • 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].)
Repair completion verification 1		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.
Repair completion verification 2		No	DTC troubleshooting completed.