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DTC P0140:00 [PCM (SKYACTIV-X)]

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Note

•  To determine the malfunctioning part, proceed with the diagnostics from "Function Inspection Using M-MDS".

Details On DTCs

Description	HO2S circuit no activity detected
Detection condition	Determination conditions	•  With the estimated temperature of the HO2S element exceeding the specified value, a condition in which the HO2S signal voltage is less than the specified value continues for the specified period.
	Preconditions	•  Battery voltage: above 11 V*1 •  The following DTCs are not detected: ―  HO2S: P0137:00 and P0138:00 ―  ECT sensor No.1: P0117:00 and P0118:00 ―  MAF sensor: P0100:00, P0101:00 and U060F:00 *1: Standard can be verified by displaying PIDs using M-MDS
	Drive cycle	•  2
	Self test type	•  CMDTC self test
	Sensor used	•  HO2S
Fail-safe function	•  Inhibits the EGR control.
Vehicle status when DTCs are output	•  Not applicable
Possible cause	•  HO2S signal line error ―  HO2S connector or terminals malfunction ―  PCM connector or terminals malfunction ―  Short to ground in HO2S signal circuit ―  Open circuit in HO2S signal circuit •  HO2S incorrect installation •  HO2S malfunction •  Exhaust gas leakage from exhaust system (between A/F sensor and HO2S) •  Insufficient engine compression •  HO2S heater malfunction •  PCM malfunction

Function Explanation (DTC Detection Outline)

Repeatability Verification Procedure

PID Item/Simulation Item Used In Diagnosis

PID/DATA monitor item table

Function Inspection Using M-MDS

Step	Inspection	Results	Action
1	PURPOSE: 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.
2	PURPOSE: 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.
3	PURPOSE: VERIFY CONNECTOR CONNECTIONS •  Start the engine. •  Access the following PIDs using the M-MDS: (See PID/DATA MONITOR INSPECTION.) ―  HO2S_HEAT ―  HO2S_OUT_VOLT •  When the following parts are shaken, does the PID value include a PID item which has changed? ―  HO2S ―  PCM	Yes	Repair or replace the applicable connector parts. Go to Troubleshooting Diagnostic Procedure to perform the repair completion verification.
		No	Go to the next step.
4	PURPOSE: VERIFICATION IF MALFUNCTION CAUSED BY HO2S •  Start the engine and idle it. •  Access the HO2S_OUT_VOLT PID using the M-MDS. (See PID/DATA MONITOR INSPECTION.) •  Is the HO2S_OUT_VOLT PID value normal? (See PID/DATA MONITOR TABLE [PCM (SKYACTIV-X)].)	Yes	Go to the next step.
		No	Go to Troubleshooting Diagnostic Procedure to perform the procedure from Step 1.
5	PURPOSE: VERIFICATION IF MALFUNCTION CAUSED BY HO2S HEATER •  Start the engine and idle it. •  Access the HO2S_HEAT PID using the M-MDS. (See PID/DATA MONITOR INSPECTION.) •  Is the HO2S_HEAT PID value normal? (See PID/DATA MONITOR TABLE [PCM (SKYACTIV-X)].)	Yes	Go to Troubleshooting Diagnostic Procedure to perform the procedure from Step 1.
		No	Go to Troubleshooting Diagnostic Procedure to perform the procedure from Step 9.

Troubleshooting Diagnostic Procedure

―  Perform an inspection of the HO2S signal line-related parts.

―  Verify the condition of the HO2S installation and perform a unit inspection.

―  Perform an exhaust system parts inspection.

―  Perform an inspection of the engine compression.

―  Perform an inspection of the HO2S heater.

―  Verify that the primary malfunction is resolved and there are no other malfunctions.

Step	Inspection	Results	Action
1	PURPOSE: INSPECT HO2S CONNECTOR FOR MALFUNCTION •  Inspect the applicable connector and terminal. (See CONNECTOR INSPECTION.) •  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.
2	PURPOSE: INSPECT PCM CONNECTOR FOR MALFUNCTION •  Inspect the applicable connector and terminal. (See CONNECTOR INSPECTION.) •  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.
3	PURPOSE: INSPECT HO2S SIGNAL CIRCUIT FOR SHORT TO GROUND •  Inspect the applicable circuit for a short to ground. (See CIRCUIT INSPECTION.) •  Is the circuit normal?	Yes	Go to the next step.
		No	Repair or replace the malfunctioning location and perform the repair completion verification.
4	PURPOSE: INSPECT HO2S SIGNAL CIRCUIT FOR OPEN CIRCUIT •  Inspect the applicable circuit for open circuit. (See CIRCUIT INSPECTION.) •  Is the circuit normal?	Yes	Go to the next step.
		No	Repair or replace the malfunctioning location and perform the repair completion verification.
5	PURPOSE: VERIFY IF HO2S IS INSTALLED CORRECTLY •  Verify the HO2S installation condition. (Installation angle, tightening torque value) (See HEATED OXYGEN SENSOR (HO2S) REMOVAL/INSTALLATION [SKYACTIV-X 2.0].) •  Is the installation condition normal?	Yes	Go to the next step.
		No	Correctly install the HO2S and perform the repair completion verification. (See HEATED OXYGEN SENSOR (HO2S) REMOVAL/INSTALLATION [SKYACTIV-X 2.0].)
6	PURPOSE: INSPECT HO2S FOR MALFUNCTION •  Inspect the applicable part. (See HEATED OXYGEN SENSOR (HO2S) INSPECTION [SKYACTIV-X 2.0].) •  Is the part normal?	Yes	Go to the next step.
		No	Repair or replace the malfunctioning location and perform the repair completion verification. (See HEATED OXYGEN SENSOR (HO2S) REMOVAL/INSTALLATION [SKYACTIV-X 2.0].)
7	PURPOSE: VERIFY IF MALFUNCTION RELATED TO EMISSION SYSTEM AFFECTS HO2S SIGNAL •  Verify the exhaust gas leakage from the exhaust system. (between A/F sensor and HO2S) •  Is there any malfunction?	Yes	Repair or replace the malfunctioning location and perform the repair completion verification.
		No	Go to the next step.
8	PURPOSE: VERIFY IF MALFUNCTION RELATED TO ENGINE COMPRESSION AFFECTS DIAGNOSTIC RESULTS •  Inspect the engine compression. (See COMPRESSION INSPECTION [SKYACTIV-X 2.0].) •  Are compression pressures within specification?	Yes	Go to the next step.
		No	Replace or overhaul the engine and perform the repair completion verification.
9	PURPOSE: INSPECT HO2S HEATER FOR MALFUNCTION •  Inspect the applicable part. (See HEATED OXYGEN SENSOR (HO2S) INSPECTION [SKYACTIV-X 2.0].) •  Is the part normal?	Yes	Go to the next step.
		No	Repair or replace the malfunctioning location and perform the repair completion verification. (See HEATED OXYGEN SENSOR (HO2S) REMOVAL/INSTALLATION [SKYACTIV-X 2.0].)
Repair completion verification 1	PURPOSE: 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. ―  Implement the repeatability verification procedure. (See Repeatability Verification Procedure.) •  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-X 2.0].)
		No	Go to the next step.
Repair completion verification 2	PURPOSE: 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.