FixVault

Diagnostic Procedure

NO. 5 ENGINE STALLS-AFTER START/AT IDLE (SKYACTIV-G 2.5T) DIAGNOSTIC PROCEDURE

STEP INSPECTION RESULTS ACTION
1 VERIFY TIMING OCCURRING MALFUNCTION
  • Verify the symptom.
  • Does the malfunction symptom occur just after the engine is started?
Yes Perform the symptom troubleshooting "NO. 4 HARD TO START/LONG CRANK/ERRATIC START/ERRATIC CRANK".
(See NO. 4 Hard To Start/Long Crank/Erratic Start/Erratic Crank .)
No Go to the next step.
2 VERIFY IF MALFUNCTION INCLUDES ROUGH IDLING
  • Verify the symptom.
  • Does the engine idle rough?
Yes Perform the symptom troubleshooting "NO. 8 ENGINE RUNS ROUGH/ROLLING IDLE".
(See NO. 8 Engine Runs Rough/Rolling Idle .)
No Go to the next step.
3 VERIFY IF MALFUNCTION CAUSE IS OVERHEATING
CAUTION:
  • While performing this step, always operate the vehicle in a safe and lawful manner.
  • When the M-MDS is used to observe monitor system status while driving, be sure to have another technician with you, or record the data in the M-MDS using the PID/DATA MONITOR AND RECORD capturing function and inspect later.
  • Access the ECT PID using the M-MDS. (See On-Board Diagnostic Test .)
  • Is the ECT PID value less than 116 °C {241 °F} during driving?
Yes Go to the next step.
No The cause of this concern could be from the cooling system overheating.
4 VERIFY PCM DTC Yes Go to the applicable DTC inspection.
(See DTC TABLE [PCM (SKYACTIV-G 2.5T)] .)
No Go to the next step.
5 VERIFY CURRENT INPUT SIGNAL STATUS
CAUTION:
  • While performing this step, always operate the vehicle in a safe and lawful manner.
  • When the M-MDS is used to observe monitor system status while driving, be sure to have another technician with you, or record the data in the M-MDS using the PID/DATA MONITOR AND RECORD capturing function and inspect later.
  • Access the following PIDs using the M-MDS: (See On-Board Diagnostic Test .)
    • APP1
    • APP2
    • ECT
    • MAF
    • MAP
    • MAP_V
    • O2S11
    • O2S12
    • SHRTFT1
      • LONGFT1
  • Do the PIDs indicate the correct values under the trouble condition? (See PCM Inspection .)
Yes Go to the next step.
No APP1, APP2 PIDs are not as specified:
ECT PID is not as specified:
MAF PID is not as specified:
MAP, MAP_V PIDs are not as specified:
O2S11, SHRTFT1, LONGFT1 PIDs are not as specified:
O2S12 PID is not as specified:
6 INSPECT PCM GROUND CIRCUIT FOR OPEN CIRCUIT
  • Main relay is removed.
  • Verify that the PCM connector is disconnected.
  • Inspect for continuity between the following harnesses:
    • PCM terminal 2S(wiring harness-side)-Body ground
    • PCM terminal 2T (wiring harness-side)-Body ground
      • PCM terminal 1CK(wiring harness-side)-Body ground
  • Is there continuity?
Yes Refer to the applicable service information and verify whether or not there is a common connector between the following terminals:
  • PCM terminal 2S(wiring harness-side)-Body ground
  • PCM terminal 2T (wiring harness-side)-Body ground
  • PCM terminal 1CK(wiring harness-side)-Body ground

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:
  • Inspect for the following:
    • Open circuit between PCM and body ground
    • Loose or lifting ground point
      • Repair or replace the malfunctioning part.

Go to Step 30.
No Go to the next step.
7 INSPECT PCM POWER SUPPLY CIRCUIT FOR OPEN CIRCUIT
  • Main relay is removed.
  • Verify that the PCM connector is disconnected.
  • Inspect for continuity between the following terminals (wiring harness-side):
    • Main relay terminal C-PCM terminal 2S
    • Main relay terminal C-PCM terminal 2T
      • Main relay terminal C-PCM terminal 1CK
  • Is there continuity?
Yes Go to the next step.
No Refer to the applicable service information and verify whether or not there is a common connector between the following terminals:
  • Main relay terminal C-PCM terminal 2S
  • Main relay terminal C-PCM terminal 2T
  • Main relay terminal C-PCM terminal 1CK

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 30.
8 INSPECT A/C CUT-OFF CONTROL SYSTEM OPERATION Yes Go to the next step.
No Perform the symptom troubleshooting "NO. 23 A/C DOES NOT WORK SUFFICIENTLY" and "NO. 24 A/C IS ALWAYS ON OR A/C COMPRESSOR RUNS CONTINUOUSLY". (See NO. 23 A/C Does Not Work Sufficiently .)
(See NO. 24 A/C Is Always On Or A/C Compressor Runs Continuously .)
9 DETERMINE IF MALFUNCTION CAUSE IS DRIVE-BY-WIRE CONTROL SYSTEM OR OTHER
  • Will the engine run smoothly at part throttle?
Yes Go to Step 11.
No Go to the next step.
10 INSPECT DRIVE-BY-WIRE CONTROL SYSTEM OPERATION Yes Visually inspect the throttle body (damage/scratching).
  • If there is any malfunction:
    • Repair or replace the malfunctioning part according to the inspection results.
  • If there is no malfunction:
    • Go to the next step.
No Repair or replace the malfunctioning part according to the inspection results.
11 INSPECT PURGE CONTROL SYSTEM OPERATION Yes Go to the next step.
No Repair or replace the malfunctioning part according to the inspection results.
12 INSPECT MAF SENSOR GROUND CIRCUIT FOR OPEN CIRCUIT
  • Inspect the MAF sensor for the following:
    • MAF sensor terminal B voltage (ground circuit)
  • Is there any malfunction?
Yes Repair or replace the suspected wiring harness.
No Go to the next step.
13 INSPECT PCM FOR POOR GROUND
  • Verify the PCM ground point condition.
  • Is there any ground point loose or lifting in the PCM?
Yes Repair the ground point.
No Go to the next step.
14 INSPECT RELATED PART CONDITION Yes Service if necessary.
  • Repeat this step.
No Go to the next step.
15 INSPECT FUEL PRESSURE (HIGH-SIDE)
  • Start the engine and warm it up completely.
  • Access the FUEL_PRES PID using the M-MDS at idle. (See On-Board Diagnostic Test .)
  • Is the FUEL_PRES PID value approx. 3 MPa {31 kgf/cm2 , 435 psi}?
Yes Go to Step 19.
No Lower than 3 MPa {31 kgf/cm2 , 435 psi}:
Higher than 3 MPa {31 kgf/cm2 , 435 psi}:
  • Go to the next step.
16 DETERMINE IF MALFUNCTION CAUSE IS FUEL PRESSURE SENSOR OR HIGH PRESSURE FUEL PUMP
  • Is the vehicle acceleration performance normal?
Yes Go to the next step.
No Go to Step 18.
17 INSPECT HIGH FUEL PRESSURE SENSOR Yes Replace the fuel distributor.
(See Fuel Injector Removal/Installation .)
No Go to Step 19.
18 INSPECT SPILL VALVE CONTROL SOLENOID VALVE CONTROL CIRCUIT FOR SHORT TO GROUND
  • Switch the ignition off.
  • Disconnect the high pressure fuel pump and PCM connectors.
  • Inspect for continuity between high pressure fuel pump terminal A (wiring harness-side) and body ground.
  • Is there continuity?
Yes Refer to the applicable service information and verify whether or not there is a common connector between high pressure fuel pump terminal A and PCM terminal 1EE.
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 malfunction remains:
No Replace the high pressure fuel pump.
(See High Pressure Fuel Pump Removal/Installation .)
19 INSPECT FUEL PRESSURE (LOW-SIDE)
  • Connect the fuel pressure gauge between fuel pump and high pressure fuel pump.
  • Measure the low side fuel pressure. (See Fuel Line Pressure Inspection .)
  • Is the low side fuel pressure within specification?

Specification:
  • 545-695 kPa {5.56-7.08 kgf/cm2 , 79.1-100.0 psi}
Yes Go to the next step.
No Inspect the following:
  • Fuel line restriction
  • Fuel filter clogged
    • If there is any malfunction:
      • Repair or replace the malfunctioning part according to the inspection results.
    • If there is no malfunction:
20 INSPECT FUEL INJECTOR OPERATION Yes Go to the next step.
No Repair or replace the malfunctioning part according to the inspection results.
21 INSPECT ENGINE COMPRESSION
  • Measure the compression pressure for each cylinder. (See Compression Inspection .)
  • Are compression pressures within specification?
Yes Go to Step 27.
No Go to the next step.
22 INSPECT ELECTRIC VARIABLE VALVE TIMING DRIVER Yes Replace the electric variable valve timing motor/driver.
(See Electric Variable Valve Timing Motor/Driver Removal/Installation .)
No Go to the next step.
23 INSPECT ELECTRIC VARIABLE VALVE TIMING MOTOR Yes Replace the electric variable valve timing motor/driver.
(See Electric Variable Valve Timing Motor/Driver Removal/Installation .)
No Go to the next step.
24 INSPECT ELECTRIC VARIABLE VALVE TIMING ACTUATOR Yes Replace the electric variable valve timing actuator.
(See Electric Variable Valve Timing Actuator, Hydraulic Variable Valve Timing Actuator Removal/Installation .)
No Go to the next step.
25 INSPECT HYDRAULIC VARIABLE VALVE TIMING CONTROL SYSTEM OPERATION Yes Repair or replace the malfunctioning part according to the inspection results.
No Go to the next step.
26 INSPECT FOR MALFUNCTION DUE TO DEVIATED VALVE TIMING Yes Inspect for the following engine internal parts:
  • Cylinder
  • Piston ring
  • Intake valve
  • Exhaust valve
  • Such as cylinder head gasket
    • If there is any malfunction:
      • Repair or replace the malfunctioning part according to the inspection results.
No Adjust the valve timing to the correct timing.
27 INSPECT IGNITION SYSTEM OPERATION Yes Go to the next step.
No Repair or replace the malfunctioning part according to the inspection results.
28 INSPECT EXHAUST SYSTEM FOR RESTRICTION
  • Inspect for restriction in the exhaust system and the TWC.
  • Is there any restriction?
Yes Repair or replace the malfunctioning part according to the inspection results.
No Go to the next step.
29 INSPECT IF MALFUNCTION CAUSE IS PCV VALVE OR INJECTOR DRIVER (PCM INTEGRATED) Yes Replace the PCV valve.
(See Positive Crankcase Ventilation (PCV) Valve Removal/Installation .)
No Injector driver malfunction.
If the problem remains, overhaul the engine.
30 Verify the test results.
  • If normal, return to the diagnostic index to service any additional symptoms. (See Symptom Diagnostic Index .)
  • If a malfunction remains, inspect the related Service Information and perform the repair or diagnosis.
    • If the vehicle is repaired, troubleshooting is completed.
      • If the vehicle is not repaired or additional diagnostic information is not available, replace the PCM. (See PCM Removal/Installation .)