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Function Inspection Using M-MDS

DTC P0171:00 (PCM (SKYACTIV-G 2.0)) DIAGNOSTIC PROCEDURE

STEP INSPECTION RESULTS ACTION
1 PURPOSE: VERIFY RELATED REPAIR INFORMATION AVAILABILITY 
  • Verify related Service Bulletins and/or on-line repair information availability.
  • Is any related repair information available?
 Yes Perform repair or diagnosis according to the available repair information.
  • If the vehicle is not repaired, go to the next step.
No Go to the next step.
2 PURPOSE: IDENTIFY TRIGGER DTC FOR FREEZE FRAME DATA 
  • Is the DTC P0171:00 on FREEZE FRAME DATA?
 Yes Go to the next step.
No Go to the troubleshooting procedure for DTC on FREEZE FRAME DATA.
(See DTC TABLE [PCM (SKYACTIV-G 2.0)] .)
3 PURPOSE: RECORD VEHICLE STATUS AT TIME OF DTC DETECTION TO UTILIZE WITH REPEATABILITY VERIFICATION 
NOTE:
  • Recording can be facilitated using the screen capture function of the PC.
  • Record the FREEZE FRAME DATA/snapshot data on the repair order.
 - Go to the next step.
4 PURPOSE: VERIFY IF INPUT SIGNAL TO PCM AFFECTS FUEL INJECTION  Yes Inspect the suspected sensor and related wiring harness.
  • If there is any malfunction:
    • Repair or replace the malfunctioning part.
    • Go to Troubleshooting Diagnostic Procedure to perform the procedure from Step 19.
  • If there is no malfunction:
    • Go to the next step.
No Go to the next step.
5 PURPOSE: VERIFY CONNECTOR CONNECTIONS 
  • Start the engine.
  • Access the following PIDs using the M-MDS: (See ON-BOARD DIAGNOSTIC TEST [PCM (SKYACTIV-G 2.0)] .)
    • FUEL_PRES
    • FP
    • EVAPCP
    • MAF
    • MAP
    • MAP_V
    • IAT2
    • VT_EX_ACT
    • VT_IN_ACT
  • When the following parts are shaken, does the PID value include a PID item which has changed?
    • Fuel pressure sensor
    • Fuel pump
    • Purge solenoid valve
    • MAF sensor
    • MAP sensor/IAT sensor No. 2
    • OCV
    • Electric variable valve timing motor/driver
    • PCM
 Yes Repair or replace the applicable connector parts.
Go to Troubleshooting Diagnostic Procedure to perform the procedure from Step 19.
No Go to the next step.
6 PURPOSE: VERIFY FUEL PRESSURE (HIGH-SIDE) MALFUNCTION 
  • Switch the ignition off.
  • Reconnect all disconnected connectors.
  • Start the engine and idle it.
  • Access the FUEL PRES PID using the M-MDS. (See ON-BOARD DIAGNOSTIC TEST [PCM (SKYACTIV-G 2.0)] .)
  • Is the FUEL_PRES PID value approx. 10 MPa {102 kgf/cm2 , 1450 psi}?
 Yes Go to the next step.
No FUEL_PRES PID value is lower than 10 MPa {102 kgf/cm2 , 1450 psi}:
  • Go to Troubleshooting Diagnostic Procedure to perform the procedure from Step 1.

FUEL_PRES PID value is higher than 10 MPa {102 kgf/cm2 , 1450 psi}:
  • Go to Step 8.
7 PURPOSE: VERIFY FUEL PRESSURE (LOW-SIDE) MALFUNCTION 
NOTE:
  • Verify the fuel pressure on the low pressure side with the operation of the high pressure fuel pump turned off.
  • Bleed the remaining pressure in the fuel line using the following procedure.
    1. Switch the ignition off.
    2. Disconnect the high pressure fuel pump connector.
    3. Remove the fuel pump relay. (See RELAY LOCATION .)
    4. Start the engine and wait until the engine stalls.
  • Switch the ignition off.
  • Install the fuel pump relay.
  • Switch the ignition ON (engine off).
  • Display PID FUEL_PRES and simulation item FP using the M-MDS. (See ON-BOARD DIAGNOSTIC TEST [PCM (SKYACTIV-G 2.0)] .)
  • Turn simulation item FP on.
  • Is the FUEL PRES PID value 425-505 kPa {4.34-5.14 kgf/cm2 , 61.7-73.2 psi}?
 Yes Go to the next step.
No Go to Troubleshooting Diagnostic Procedure to perform the procedure from Step 5.
8 PURPOSE: VERIFY IF MALFUNCTION CAUSED BY FUEL INJECTOR IMPROPER OPERATION 
  • Switch the ignition off.
  • Reconnect all disconnected connectors.
  • Start the engine and idle it.
  • Access the following simulation items using the M-MDS: (See ON-BOARD DIAGNOSTIC TEST [PCM (SKYACTIV-G 2.0)] .)
    • INJ_1
    • INJ_2
    • INJ_3
    • INJ_4
  • Turn each fuel injector from on to off using the simulation items.
  • Does the vibration during idling worsen?
 Yes Go to the next step.
No Go to Troubleshooting Diagnostic Procedure to perform the procedure from Step 6.
9 PURPOSE: VERIFY IF MALFUNCTION CAUSED BY PURGE SOLENOID VALVE IMPROPER OPERATION  Yes Go to the next step.
No Go to Troubleshooting Diagnostic Procedure to perform the procedure from Step 7.
10 PURPOSE: VERIFY MAF SENSOR  Yes Go to the next step.
No Go to Troubleshooting Diagnostic Procedure to perform the procedure from Step 9.
11 PURPOSE: VERIFY MAP SENSOR  Yes Go to the next step.
No Go to Troubleshooting Diagnostic Procedure to perform the procedure from Step 11.
12 PURPOSE: VERIFY INTAKE VALVE TIMING 
  • Start the engine and idle it.
  • Access the following PIDs using the M-MDS: (See ON-BOARD DIAGNOSTIC TEST [PCM (SKYACTIV-G 2.0)] .)
    • VT_IN_ACT
    • VT_IN_DES
  • Depress the accelerator pedal to increase the engine speed.
  • Does the monitor value of the PID item VT_IN_ACT conform to the VT_IN_DES PID value?
 Yes Go to the next step.
No Go to Troubleshooting Diagnostic Procedure to perform the procedure from Step 13.
13 PURPOSE: VERIFY EXHAUST VALVE TIMING 
  • Start the engine and idle it.
  • Access the following PIDs using the M-MDS: (See ON-BOARD DIAGNOSTIC TEST [PCM (SKYACTIV-G 2.0)] .)
    • VT EX ACT
    • VT_EX_DES
  • Perform the following:
    1. Warm up the engine to allow the engine coolant temperature to reach 80°C {176°F} or more.
    2. Shift to 2nd gear (MT)/D position (AT) and rapidly accelerate the vehicle to 50 km/h {31 mph} (to operate hydraulic variable valve timing control).
    3. Decelerate to idling.
    4. Shift to 2nd gear (MT)/D position (AT) and rapidly accelerate the vehicle to 50 km/h {31 mph} again.
  • Does the monitor value of the PID item VT_EX_ACT conform to the VT_EX_DES PID value?
 Yes Go to the next step.
No Go to Troubleshooting Diagnostic Procedure to perform the procedure from Step 16.
14 PURPOSE: VERIFY A/F SENSOR  Yes Go to the next step.
No Go to Troubleshooting Diagnostic Procedure to perform the procedure from Step 17.
15 PURPOSE: VERIFY DTC  Yes Go to the applicable DTC inspection.
(See DTC TABLE [PCM (SKYACTIV-G 2.0)]
Go to Troubleshooting Diagnostic Procedure to perform the procedure from Step 1.
No Go to Troubleshooting Diagnostic Procedure to perform the procedure from Step 1.
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