DTC P0154:00 [SKYACTIV-D 2.2]

id0102s4147200

DTC P0154:00

Atmosphere learning malfunction in A/F sensor circuit

DETECTION CONDITION

•  The difference in the oxygen concentration between atmosphere and the A/F sensor output value is 35 % or more for a continuous 5 s.

MONITORING CONDITIONS

―  A/F sensor feedback correction is actuated

Diagnostic support note

•  This is an intermittent monitor (A/F sensor).

•  The check engine light illuminates if the PCM detects the above malfunction condition during the first drive cycle.

•  FREEZE FRAME DATA (Mode 2)/Snapshot data is available.

•  DTC is stored in the PCM memory.

FAIL-SAFE FUNCTION

•  PCM restricts engine torque.

•  Inhibits the EGR control.

•  Inhibits the diesel particulate filter regeneration control.

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

•  PCM restricts engine-transaxle integration control.

POSSIBLE CAUSE

•  A/F sensor heater malfunction

•  Erratic signal from A/F sensor

―  A/F sensor loose

―  Exhaust system leakage

•  A/F sensor connector or terminals malfunction

•  Short to ground in wiring harness between the following terminals:

―  A/F sensor terminal A—PCM terminal 1H

―  A/F sensor terminal B—PCM terminal 1I

•  PCM connector or terminals malfunction

•  Open circuit in wiring harness between the following terminals:

―  A/F sensor terminal A—PCM terminal 1H

―  A/F sensor terminal B—PCM terminal 1I

•  Engine malfunction

―  Insufficient engine compression

―  Engine coolant leakage to combustion chamber

•  A/F sensor malfunction

―  A/F sensor deterioration

•  Engine oil malfunction

―  Oil going up

―  Oil going down

•  PCM malfunction

DTC P0154:00	Atmosphere learning malfunction in A/F sensor circuit
DETECTION CONDITION	• The difference in the oxygen concentration between atmosphere and the A/F sensor output value is 35 % or more for a continuous 5 s. MONITORING CONDITIONS ― A/F sensor feedback correction is actuated Diagnostic support note • This is an intermittent monitor (A/F sensor). • The check engine light illuminates if the PCM detects the above malfunction condition during the first drive cycle. • FREEZE FRAME DATA (Mode 2)/Snapshot data is available. • DTC is stored in the PCM memory.
FAIL-SAFE FUNCTION	• PCM restricts engine torque. • Inhibits the EGR control. • Inhibits the diesel particulate filter regeneration control. • Inhibits engine-stop by operating the i-stop function. • PCM restricts engine-transaxle integration control.
POSSIBLE CAUSE	• A/F sensor heater malfunction • Erratic signal from A/F sensor ― A/F sensor loose ― Exhaust system leakage • A/F sensor connector or terminals malfunction • Short to ground in wiring harness between the following terminals: ― A/F sensor terminal A—PCM terminal 1H ― A/F sensor terminal B—PCM terminal 1I • PCM connector or terminals malfunction • Open circuit in wiring harness between the following terminals: ― A/F sensor terminal A—PCM terminal 1H ― A/F sensor terminal B—PCM terminal 1I • Engine malfunction ― Insufficient engine compression ― Engine coolant leakage to combustion chamber • A/F sensor malfunction ― A/F sensor deterioration • Engine oil malfunction ― Oil going up ― Oil going down • PCM malfunction

Diagnostic Procedure

STEP	INSPECTION		ACTION
1	IDENTIFY TRIGGER DTC FOR FREEZE FRAME DATA (MODE 2) • Perform the Freeze Frame PID Data Access Procedure. (See ON-BOARD DIAGNOSTIC TEST [SKYACTIV-D 2.2].) • Is the DTC P0154:00 on FREEZE FRAME DATA (Mode 2)?	Yes	Go to the next step.
1		No	Go to the troubleshooting procedure for DTC on FREEZE FRAME DATA (Mode 2). (See DTC TABLE [SKYACTIV-D 2.2].)
2	VERIFY FREEZE FRAME DATA (MODE 2)/SNAPSHOT DATA AND DIAGNOSTIC MONITORING TEST RESULTS HAVE BEEN RECORDED • Have the FREEZE FRAME DATA (Mode 2)/snapshot data and DIAGNOSTIC MONITORING TEST RESULTS (A/F sensor related) been recorded?	Yes	Go to the next step.
2		No	Record the FREEZE FRAME DATA (Mode 2)/snapshot data and DIAGNOSTIC MONITORING TEST RESULTS on the repair order, then go to the next step.
3	VERIFY RELATED SERVICE INFORMATION AVAILABILITY • Verify related Service Information availability. • Is any related Service Information available?	Yes	Perform repair or diagnosis according to the available Service Information. • If the vehicle is not repaired, go to the next step.
3		No	Go to the next step.
4	VERIFY RELATED PENDING CODE AND/OR DTC • Switch the ignition off, then ON (engine off). • Perform the Pending Trouble Code Access Procedure and DTC Reading Procedure. (See ON-BOARD DIAGNOSTIC TEST [SKYACTIV-D 2.2].) • Are any other PENDING CODEs and/or DTCs present?	Yes	Go to the applicable PENDING CODE or DTC inspection. (See DTC TABLE [SKYACTIV-D 2.2].)
4		No	Go to the next step.
5	INSPECT A/F SENSOR HEATER • Inspect the A/F sensor heater. (See AIR FUEL RATIO (A/F) SENSOR INSPECTION [SKYACTIV-D 2.2].) • Is there any malfunction?	Yes	Replace the A/F sensor, then go to Step 16. (See AIR FUEL RATIO (A/F) SENSOR REMOVAL/INSTALLATION [SKYACTIV-D 2.2].)
5		No	Go to the next step.
6	INSPECT A/F SENSOR • Inspect the A/F sensor. (See AIR FUEL RATIO (A/F) SENSOR INSPECTION [SKYACTIV-D 2.2].) • Is there any malfunction?	Yes	Go to the next step.
6		No	Go to Step 9.
7	INSPECT INSTALLATION OF A/F SENSOR • Inspect installation of A/F sensor. • Is the A/F sensor installed securely?	Yes	Go to the next step.
7		No	Retighten the A/F sensor, then go to Step 16. (See AIR FUEL RATIO (A/F) SENSOR REMOVAL/INSTALLATION [SKYACTIV-D 2.2].)
8	INSPECT EXHAUST SYSTEM FOR LEAKAGE • Visually inspect for exhaust gas leakage in the exhaust system. • Is there any leakage?	Yes	Repair or replace the malfunctioning part according to the inspection results, then go to Step 16.
8		No	Replace the A/F sensor, then go to Step 16. (See AIR FUEL RATIO (A/F) SENSOR REMOVAL/INSTALLATION [SKYACTIV-D 2.2].)
9	INSPECT A/F SENSOR CONNECTOR CONDITION • Switch the ignition off. • Disconnect the A/F sensor connector. • Inspect for poor connection (such as damaged/pulled-out pins, corrosion). • Is there any malfunction?	Yes	Repair or replace the connector and/or terminals, then go to Step 16.
9		No	Go to the next step.
10	INSPECT A/F SENSOR CIRCUIT FOR SHORT TO GROUND • Verify that the A/F sensor connector is disconnected. • Inspect for continuity between the following terminals (wiring harness-side) and body ground: ― A/F sensor terminal A ― A/F sensor terminal B • Is there continuity?	Yes	If the short to ground circuit could be detected in the wiring harness: • Refer to the wiring diagram and verify whether or not there is a common connector between the following terminals: ― A/F sensor terminal A—PCM terminal 1H ― A/F sensor terminal B—PCM terminal 1I If there is a common connector: ― Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to ground. ― Repair or replace the malfunctioning part. If there is no common connector: ― Repair or replace the wiring harness which has a short to ground. If the short to ground circuit could not be detected in the wiring harness: • Replace the PCM (short to ground in the PCM internal circuit). (See PCM REMOVAL/INSTALLATION [SKYACTIV-D 2.2].) Go to Step 16.
10		No	Go to the next step.
11	INSPECT PCM CONNECTOR CONDITION • Disconnect the PCM connector. • Inspect for poor connection (such as damaged/pulled-out pins, corrosion). • Is there any malfunction?	Yes	Repair or replace the connector and/or terminals, then go to Step 16.
11		No	Go to the next step.
12	INSPECT A/F SENSOR CIRCUIT FOR OPEN CIRCUIT • Verify that the A/F sensor and PCM connectors are disconnected. • Inspect for continuity between the following terminals (wiring harness-side): ― A/F sensor terminal A—PCM terminal 1H ― A/F sensor terminal B—PCM terminal 1I • Is there continuity?	Yes	Go to the next step.
12		No	Refer to the wiring diagram and verify whether or not there is a common connector between the following terminals: • A/F sensor terminal A—PCM terminal 1H • A/F sensor terminal B—PCM terminal 1I If there is a common connector: • Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for an open circuit. • Repair or replace the malfunctioning part. If there is no common connector: • Repair or replace the wiring harness which has an open circuit. Go to Step 16.
13	INSPECT ENGINE COMPRESSION • Inspect the engine compression. (See COMPRESSION INSPECTION [SKYACTIV-D 2.2].) • Are compression pressures within specification? Specification: • Compression ― Standard: 2255 kPa {22.99 kgf/cm², 327.1 psi} (180 rpm) ― Minimum: 1804 kPa {18.40 kgf/cm², 261.6 psi} (180 rpm) ― Maximum difference between cylinders: 147 kPa {1.50 kgf/cm², 21.3 psi} (180 rpm)	Yes	Go to the next step.
13		No	Repair or replace the malfunctioning part according to the inspection results, then go to Step 16.
14	INSPECT SEALING OF ENGINE COOLANT PASSAGE • Perform the “ENGINE COOLANT LEAKAGE INSPECTION”. (See ENGINE COOLANT LEAKAGE INSPECTION [SKYACTIV-D 2.2].) • Does the radiator cap tester needle drop even though there is no engine coolant leakage from the radiator or the hoses?	Yes	Engine coolant leakage from the engine (between the combustion chamber and the engine coolant passage) may have occurred. • Verify the conditions of the gasket and the cylinder head. ― If there is any malfunction: • Repair or replace the malfunctioning part according to the inspection results, then go to Step 16.
14		No	Go to the next step.
15	INSPECT FOR MALFUNCTION DUE TO INTERNAL ENGINE WEAR, DAMAGE • Inspect for the following engine internal parts: ― Cylinder ― Piston ring ― Intake valve ― Exhaust valve ― Such as cylinder head gasket • Are all items normal?	Yes	Engine internal parts are normal. • Go to the next step.
15		No	Repair or replace the malfunctioning part according to the inspection results, then go to the next step.
16	VERIFY DTC TROUBLESHOOTING COMPLETED • Always reconnect all disconnected connectors. • Clear the DTC from the PCM memory using the M-MDS. (See AFTER REPAIR PROCEDURE [SKYACTIV-D 2.2].) • Perform the Drive Mode Type A. (See OBD DRIVE MODE [SKYACTIV-D 2.2].) • Perform the DTC Reading Procedure. (See ON-BOARD DIAGNOSTIC TEST [SKYACTIV-D 2.2].) • Is the PENDING CODE for this DTC present?	Yes	Repeat the inspection from Step 1. • If the malfunction recurs, replace the PCM. (See PCM REMOVAL/INSTALLATION [SKYACTIV-D 2.2].) Go to the next step.
16		No	Go to the next step.
17	VERIFY AFTER REPAIR PROCEDURE • Perform the “AFTER REPAIR PROCEDURE”. (See AFTER REPAIR PROCEDURE [SKYACTIV-D 2.2].) • Are any DTCs present?	Yes	Go to the applicable DTC inspection. (See DTC TABLE [SKYACTIV-D 2.2].)
17		No	DTC troubleshooting completed.