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DTC P026A:00 [PCM (SKYACTIV-D)]

id0102t5416800

Outline

System malfunction location

Charge air cooler efficiency below threshold

Detection condition

•  The boost air temperature after passing through the charge air cooler exceeds 120 °C {248 °F} for a continuous 10 s.

Preconditions

―  Vehicle speed: 30 km/h {19 mph} or more

―  Duty value of the electric water pump: 80 % or more

―  The amount of fluctuation in the boost air temperature before and after passing through the charge air cooler for the past 10 s: Within 50 °C {122 °F}

―  The following components are normal:

•  IAT sensor No.1

•  Battery

•  Electric water pump circuit

•  Vehicle speed signal

•  Intake shutter valve

•  HP-EGR control valve

•  LP-EGR control valve

•  Exhaust shutter valve

•  Exhaust gas reflux amount of EGR system

•  Turbocharger with variable turbine geometry

•  Speed sensor assy (turbocharger with variable turbine geometry)

•  MAP sensor

Fail-safe

•  PCM restricts engine torque.

•  Restricts the upper limit of the engine speed.

•  Inhibits the EGR control.

Possible cause

•  Improper water-cooled charge air cooler coolant level

•  Restrict air flow at radiator core

•  Restrict air flow at water-cooled charge air cooler core

•  Electric water pump malfunction (Damage of internal impeller, stuck)

•  Water-cooled charge air cooler coolant passage (including radiator) clogged

•  Boost air temperature sensor malfunction

•  PCM malfunction

System wiring diagram

•  Not applicable

Connector diagram

•  Not applicable

System malfunction location	Charge air cooler efficiency below threshold
Detection condition	• The boost air temperature after passing through the charge air cooler exceeds 120 °C {248 °F} for a continuous 10 s. Preconditions ― Vehicle speed: 30 km/h {19 mph} or more ― Duty value of the electric water pump: 80 % or more ― The amount of fluctuation in the boost air temperature before and after passing through the charge air cooler for the past 10 s: Within 50 °C {122 °F} ― The following components are normal: • IAT sensor No.1 • Battery • Electric water pump circuit • Vehicle speed signal • Intake shutter valve • HP-EGR control valve • LP-EGR control valve • Exhaust shutter valve • Exhaust gas reflux amount of EGR system • Turbocharger with variable turbine geometry • Speed sensor assy (turbocharger with variable turbine geometry) • MAP sensor
Fail-safe	• PCM restricts engine torque. • Restricts the upper limit of the engine speed. • Inhibits the EGR control.
Possible cause	• Improper water-cooled charge air cooler coolant level • Restrict air flow at radiator core • Restrict air flow at water-cooled charge air cooler core • Electric water pump malfunction (Damage of internal impeller, stuck) • Water-cooled charge air cooler coolant passage (including radiator) clogged • Boost air temperature sensor 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

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

INSPECT WATER-COOLED CHARGE AIR COOLER COOLANT LEVEL

•  Perform the “WATER-COOLED CHARGE AIR COOLER COOLANT LEVEL INSPECTION”.
(See WATER-COOLED CHARGE AIR COOLER COOLANT LEVEL INSPECTION [SKYACTIV-D 1.8].)

•  Is the coolant level within the specified?

Yes

Go to the next step.

No

Add water-cooled charge air cooler coolant, then go to repair completion verification.

5

INSPECT RADIATOR CORE CONDITION

•  Visually inspect the radiator core condition.

•  Is there damage or an object which obstructs cool airflow?

Yes

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

No

Go to the next step.

6

DETERMINE IF MALFUNCTION IS DUE TO ELECTRIC WATER PUMP STUCK

•  Inspect the electric water pump.
(See ELECTRIC WATER PUMP INSPECTION [SKYACTIV-D 1.8].)

•  Is there any malfunction?

Yes

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

(See ELECTRIC WATER PUMP REMOVAL/INSTALLATION [SKYACTIV-D 1.8].)

No

Go to the next step.

7

INSPECT BOOST AIR TEMPERATURE SENSOR FOR MALFUNCTION

•  Inspect the applicable part.
(See BOOST AIR TEMPERATURE SENSOR 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 MANIFOLD ABSOLUTE PRESSURE (MAP) SENSOR/BOOST AIR TEMPERATURE SENSOR REMOVAL/INSTALLATION [SKYACTIV-D 1.8].)

8

INSPECT WATER-COOLED CHARGE AIR COOLER CORE CONDITION

•  Visually inspect the water-cooled charge air cooler core condition.

•  Is there damage or an object which prevents intake airflow?

Yes

Clean or replace water-cooled charge air cooler as necessary, then go to the next step.

No

Inspect restrict in water-cooled charge air cooler coolant passage.

•  If malfunction is detected:

―  Repair or replace the malfunctioning part, then go to the next step.

•   If normal:

―  Go to the next step.

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 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
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	INSPECT WATER-COOLED CHARGE AIR COOLER COOLANT LEVEL • Perform the “WATER-COOLED CHARGE AIR COOLER COOLANT LEVEL INSPECTION”. (See WATER-COOLED CHARGE AIR COOLER COOLANT LEVEL INSPECTION [SKYACTIV-D 1.8].) • Is the coolant level within the specified?	Yes	Go to the next step.
4		No	Add water-cooled charge air cooler coolant, then go to repair completion verification.
5	INSPECT RADIATOR CORE CONDITION • Visually inspect the radiator core condition. • Is there damage or an object which obstructs cool airflow?	Yes	Repair or replace the malfunctioning location and perform the repair completion verification.
5		No	Go to the next step.
6	DETERMINE IF MALFUNCTION IS DUE TO ELECTRIC WATER PUMP STUCK • Inspect the electric water pump. (See ELECTRIC WATER PUMP INSPECTION [SKYACTIV-D 1.8].) • Is there any malfunction?	Yes	Repair or replace the malfunctioning location and perform the repair completion verification. (See ELECTRIC WATER PUMP REMOVAL/INSTALLATION [SKYACTIV-D 1.8].)
6		No	Go to the next step.
7	INSPECT BOOST AIR TEMPERATURE SENSOR FOR MALFUNCTION • Inspect the applicable part. (See BOOST AIR TEMPERATURE SENSOR INSPECTION [SKYACTIV-D 1.8].) • Is the part normal?	Yes	Go to the next step.
7		No	Repair or replace the malfunctioning location and perform the repair completion verification. (See MANIFOLD ABSOLUTE PRESSURE (MAP) SENSOR/BOOST AIR TEMPERATURE SENSOR REMOVAL/INSTALLATION [SKYACTIV-D 1.8].)
8	INSPECT WATER-COOLED CHARGE AIR COOLER CORE CONDITION • Visually inspect the water-cooled charge air cooler core condition. • Is there damage or an object which prevents intake airflow?	Yes	Clean or replace water-cooled charge air cooler as necessary, then go to the next step.
8		No	Inspect restrict in water-cooled charge air cooler coolant passage. • If malfunction is detected: ― Repair or replace the malfunctioning part, then go to the next step. • If normal: ― Go to the next step.
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 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].)
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.