DTC P039A:00, P03A4:00, P03AE:00, P03B8:00 [PCM (SKYACTIV-D 2.2)]

DTC P039A:00	Cylinder No. 1 compression pressure is too low
DETECTION CONDITION	• Decrease in compression pressure of each cylinder is detected during deceleration Diagnostic support note • This is a continuous monitor (other). • The check engine light does not illuminate. • FREEZE FRAME DATA/Snapshot data is available. • DTC is stored in the PCM memory.
FAIL-SAFE FUNCTION	• Temporarily inhibits engine-stop by i-stop control • Temporarily increases the engine speed when the engine is switched from the deceleration fuel cut condition to the idling fuel injection condition. • Temporarily opens the intake shutter valve and assures compression pressure.
POSSIBLE CAUSE	Note • The DTCs are a recorded past history that the PCM detected a decrease in compression pressure of each cylinder during deceleration and operated the fail-safes previously mentioned to temporarily adjust the engine condition. • If the engine malfunction continues after the vehicle was serviced, take the appropriate measures according to the diagnostic procedure because the following could be considered possible causes. • Poor engine compression • CKP sensor malfunction • Crankshaft plate damage • PCM malfunction
SYSTEM WIRING DIAGRAM	Not applicable

DTC P039A:00

Cylinder No. 1 compression pressure is too low

DTC P03A4:00

Cylinder No. 2 compression pressure is too low

DTC P03AE:00

Cylinder No. 3 compression pressure is too low

DTC P03B8:00

Cylinder No. 4 compression pressure is too low

DETECTION CONDITION

• Decrease in compression pressure of each cylinder is detected during deceleration

Diagnostic support note

• This is a continuous monitor (other).

• The check engine light does not illuminate.

• FREEZE FRAME DATA/Snapshot data is available.

• DTC is stored in the PCM memory.

FAIL-SAFE FUNCTION

• Temporarily inhibits engine-stop by i-stop control

• Temporarily increases the engine speed when the engine is switched from the deceleration fuel cut condition to the idling fuel injection condition.

• Temporarily opens the intake shutter valve and assures compression pressure.

POSSIBLE CAUSE

Note

• The DTCs are a recorded past history that the PCM detected a decrease in compression pressure of each cylinder during deceleration and operated the fail-safes previously mentioned to temporarily adjust the engine condition.

• If the engine malfunction continues after the vehicle was serviced, take the appropriate measures according to the diagnostic procedure because the following could be considered possible causes.

• Poor engine compression

• CKP sensor malfunction

• Crankshaft plate damage

• PCM malfunction

SYSTEM WIRING DIAGRAM

Not applicable

Step	Inspection	Results	Action
1	VERIFY DTC CAUSING FREEZE FRAME DATA • Is DTC P039A:00, P03A4:00, P03AE:00, or P03B8:00 causing the freeze frame data?	Yes	Go to the next step.
No	Inspect the DTC causing the freeze frame data. (See DTC TABLE [PCM (SKYACTIV-D 2.2)].)
2	RECORD VEHICLE STATUS WHEN DTC WAS DETECTED TO UTILIZE WITH REPEATABILITY VERIFICATION Note • Recording can be facilitated using the screen capture function of the PC. • Record the freeze frame data/snap shot data.	—	Go to the next step.
3	VERIFY OTHER RELATED DTCs • Switch the ignition OFF, and then switch it ON (engine off). • Display the DTCs using the M-MDS. (See ON-BOARD DIAGNOSTIC TEST [PCM (SKYACTIV-D 2.2)].) • Have DTCs other than P039A:00, P03A4:00, P03AE:00, and P03B8:00 or pending code been stored?	Yes	Repair the malfunctioning location according to the applicable DTC troubleshooting first, then go to the next step. (See DTC TABLE [PCM (SKYACTIV-D 2.2)].)
No	Go to the next step.
4	VERIFY RELATED SENSOR INPUT SIGNAL • Start the engine and warm it up. • Display the following PIDs using the M-MDS. (See ON-BOARD DIAGNOSTIC TEST [PCM (SKYACTIV-D 2.2)].) ― ECT ― IAT ― MAF ― RPM ― APP ― VSS ― FRP • Are the monitoring values normal?	Yes	Go to the next step.
No	Repair or replace the malfunctioning location, then go to Step 6.
5	VERIFY INPUT SIGNAL FROM RELATED SENSOR WHILE DRIVING UNDER LOAD • Start the engine and warm it up. • Drive the vehicle under the condition of the freeze frame data (mode 2) recorded in Step 2 and display the following PIDs using the M-MDS under this condition. (See ON-BOARD DIAGNOSTIC TEST [PCM (SKYACTIV-D 2.2)].) ― ECT ― IAT ― MAF ― RPM ― APP ― VSS ― FRP • Are the monitoring values normal?	Yes	Go to the next step.
No	Repair or replace the malfunctioning location, then go to Step 6.
6	INSPECT ENGINE COMPRESSION PRESSURE • Inspect the engine compression pressure. (See COMPRESSION INSPECTION [SKYACTIV-D 2.2].) • Is the engine compression pressure normal?	Yes	Regard it as a temporary decrease in compression pressure, then go to the next step.
No	Repair or replace the malfunctioning location, then go to the next step.
7	VERIFY THAT REPAIRS HAVE BEEN COMPLETED • Reconnect all disconnected connectors and hoses. • Refer to the [MEMORY CLEARING PROCEDURE] and clear the DTC. (See CLEARING DTC [PCM (SKYACTIV-D 2.2)].) • Start the engine and drive the vehicle under the freeze frame data/snapshot data condition. Warning • To prevent an accident, work with another person when the vehicle is being driven (one person drives vehicle, other person operates M-MDS). • Observe legal speed limits when driving the vehicle and perform the procedure in a location where safety can be assured. • Display the DTCs using the M-MDS. (See ON-BOARD DIAGNOSTIC TEST [PCM (SKYACTIV-D 2.2)].) • Has DTC P039A:00, P03A4:00, P03AE:00, or P03B8:00 been stored?	Yes	Repeat the inspection from Step 1. • If the malfunction recurs, replace the PCM, then go to the next step. (See PCM REMOVAL/INSTALLATION [SKYACTIV-D 2.2].)
No	Go to the next step.
8	VERIFY OTHER DTCs • Has any other DTC or pending code been stored?	Yes	Repair the malfunctioning location according to the applicable DTC troubleshooting. (See DTC TABLE [PCM (SKYACTIV-D 2.2)].)
No	DTC troubleshooting completed.

Step

Inspection

Results

Action

VERIFY DTC CAUSING FREEZE FRAME DATA

• Is DTC P039A:00, P03A4:00, P03AE:00, or P03B8:00 causing the freeze frame data?

Yes

Go to the next step.

Inspect the DTC causing the freeze frame data.

(See DTC TABLE [PCM (SKYACTIV-D 2.2)].)

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

Note

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

• Record the freeze frame data/snap shot data.

—

Go to the next step.

VERIFY OTHER RELATED DTCs

• Switch the ignition OFF, and then switch it ON (engine off).

• Display the DTCs using the M-MDS.

(See ON-BOARD DIAGNOSTIC TEST [PCM (SKYACTIV-D 2.2)].)

• Have DTCs other than P039A:00, P03A4:00, P03AE:00, and P03B8:00 or pending code been stored?

Yes

Repair the malfunctioning location according to the applicable DTC troubleshooting first, then go to the next step.

(See DTC TABLE [PCM (SKYACTIV-D 2.2)].)

Go to the next step.

VERIFY RELATED SENSOR INPUT SIGNAL

• Start the engine and warm it up.

• Display the following PIDs using the M-MDS.

(See ON-BOARD DIAGNOSTIC TEST [PCM (SKYACTIV-D 2.2)].)

― ECT

― IAT

― MAF

― RPM

― APP

― VSS

― FRP

• Are the monitoring values normal?

Yes

Go to the next step.

Repair or replace the malfunctioning location, then go to Step 6.

VERIFY INPUT SIGNAL FROM RELATED SENSOR WHILE DRIVING UNDER LOAD

• Start the engine and warm it up.

• Drive the vehicle under the condition of the freeze frame data (mode 2) recorded in Step 2 and display the following PIDs using the M-MDS under this condition.

(See ON-BOARD DIAGNOSTIC TEST [PCM (SKYACTIV-D 2.2)].)

― ECT

― IAT

― MAF

― RPM

― APP

― VSS

― FRP

• Are the monitoring values normal?

Yes

Go to the next step.

Repair or replace the malfunctioning location, then go to Step 6.

INSPECT ENGINE COMPRESSION PRESSURE

• Inspect the engine compression pressure.

(See COMPRESSION INSPECTION [SKYACTIV-D 2.2].)

• Is the engine compression pressure normal?

Yes

Regard it as a temporary decrease in compression pressure, then go to the next step.

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

VERIFY THAT REPAIRS HAVE BEEN COMPLETED

• Reconnect all disconnected connectors and hoses.

• Refer to the [MEMORY CLEARING PROCEDURE] and clear the DTC.

(See CLEARING DTC [PCM (SKYACTIV-D 2.2)].)

• Start the engine and drive the vehicle under the freeze frame data/snapshot data condition.

Warning

• To prevent an accident, work with another person when the vehicle is being driven (one person drives vehicle, other person operates M-MDS).

• Observe legal speed limits when driving the vehicle and perform the procedure in a location where safety can be assured.

• Display the DTCs using the M-MDS.

(See ON-BOARD DIAGNOSTIC TEST [PCM (SKYACTIV-D 2.2)].)

• Has DTC P039A:00, P03A4:00, P03AE:00, or P03B8:00 been stored?

Yes

Repeat the inspection from Step 1.

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

(See PCM REMOVAL/INSTALLATION [SKYACTIV-D 2.2].)

Go to the next step.

VERIFY OTHER DTCs

• Has any other DTC or pending code been stored?

Yes

Repair the malfunctioning location according to the applicable DTC troubleshooting.

(See DTC TABLE [PCM (SKYACTIV-D 2.2)].)

DTC troubleshooting completed.