ACCELERATION MALFUNCTION [SKYACTIV-D]
id1103sc002600
Troubleshooting item |
Acceleration malfunction |
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Description
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• Acceleration from i-stop is not smooth.
• Suppresses (shock) when accelerating vehicle from i-stop.
• Engine vibration increases when engine is restarted.
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Possible cause
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A/C system malfunction
• Improper A/C system operation
Hill launch assist function system (DSC) malfunction
• False detection of inclination angle (cannot calculate correct road slope)
• False detection of brake fluid pressure
• Cannot maintain brake fluid pressure
ATX system malfunction
• Electric AT oil pump malfunction (operation malfunction, insufficient pressure)
• ATX malfunction
• Lack of ATF
Brake system malfunction
• Brake dragging
Engine system malfunction
• Drive belt shear, deviation, or wear
• Fuel injection system malfunction
• Poor fuel quality
• Mechanical (engine) malfunction
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Diagnostic procedure
Step |
Inspection |
Results |
Action |
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1
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DETERMINE IF MALFUNCTION CAUSED BY A/C SYSTEM OPERATION
• Verify the A/C system operation.
• Is the A/C system operation normal?
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Yes
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Go to the next step.
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No
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Perform the symptom troubleshooting “A/C DOES NOT WORK SUFFICIENTLY” and “A/C IS ALWAYS ON OR A/C COMPRESSOR RUNS CONTINUOUSLY”.
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2
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DETERMINE IF MALFUNCTION CAUSED BY ATX BODY
• Compare the malfunction symptom with the i-stop system stop condition.
• Is there any shock or slippage during acceleration with the i-stop system disabled?
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Yes
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Perform the applicable symptom troubleshooting procedure.
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No
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Go to the next step.
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3
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VERIFY DTC
• Perform the DTC inspection for the following modules.
(See DTC INSPECTION.)
• Are any DTCs displayed?
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Yes
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Repair the malfunctioning location according to the applicable DTC troubleshooting.
(See DTC TABLE [PCM (SKYACTIV-D)].)
(See DTC TABLE [DSC HU/CM (E)].)
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No
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Go to the next step.
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4
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DETERMINE IF MALFUNCTION CAUSE IS BRAKE FLUID PRESSURE SENSOR SIGNAL OR OTHER
• Put the vehicle in an i-stop condition (engine stopped).
• Monitor the PCM PID BRK_FLD_PRES using the M-MDS while the brake is depressed and held with the i-stop function operating.
(See PID/DATA MONITOR INSPECTION.)
• Does the monitoring value change?
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Yes
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Refer to the controller area network (CAN) malfunction diagnosis flow to inspect for a CAN communication error.
• If the CAN communication is normal, repeat the inspection from Step 1.
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No
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Go to the next step.
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5
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INSPECT ELECTRIC AT OIL PUMP RELAY FOR MALFUNCTION
• Inspect the applicable part.
(See RELAY INSPECTION.)
• Is the part normal?
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Yes
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Go to the next step.
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No
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Repair or replace the malfunctioning location and perform the repair completion verification 1.
(See RELAY LOCATION [(E)].)
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6
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INSPECT ELECTRIC AT OIL PUMP RELAY POWER SUPPLY CIRCUIT FOR SHORT TO GROUND OR OPEN CIRCUIT
• Inspect the applicable circuit for an open circuit and short to ground.
(See CIRCUIT INSPECTION.)
• Is the circuit normal?
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Yes
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Go to the next step.
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No
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Repair or replace the malfunctioning location and perform the repair completion verification 1.
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7
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INSPECT ELECTRIC AT OIL PUMP CONNECTOR FOR MALFUNCTION
• Inspect the applicable connector and terminal.
(See CONNECTOR INSPECTION.)
• Are the connector and terminal normal?
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Yes
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Go to the next step.
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No
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Repair or replace the malfunctioning location and perform the repair completion verification 1.
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8
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INSPECT ELECTRIC AT OIL PUMP GROUND CIRCUIT FOR OPEN CIRCUIT
• Inspect the applicable circuit for an open circuit.
(See CIRCUIT INSPECTION.)
• Is the circuit normal?
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Yes
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Go to the next step.
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No
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Repair or replace the malfunctioning location and perform the repair completion verification 1.
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9
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INSPECT ELECTRIC AT OIL PUMP POWER SUPPLY CIRCUIT FOR SHORT TO GROUND
• Inspect the applicable circuit for a short to ground.
(See CIRCUIT INSPECTION.)
• Is the circuit normal?
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Yes
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Go to the next step.
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No
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Repair or replace the malfunctioning location and perform the repair completion verification 1.
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10
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INSPECT ELECTRIC AT OIL PUMP POWER SUPPLY CIRCUIT FOR OPEN CIRCUIT
• Inspect the applicable circuit for an open circuit.
(See CIRCUIT INSPECTION.)
• Is the circuit normal?
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Yes
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Go to the next step.
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No
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Repair or replace the malfunctioning location and perform the repair completion verification 1.
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11
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INSPECT TCM CONNECTOR FOR MALFUNCTION
• Inspect the applicable connector and terminal.
(See CONNECTOR INSPECTION.)
• Are the connector and terminal normal?
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Yes
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Go to the next step.
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No
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Repair or replace the malfunctioning location and perform the repair completion verification 1.
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12
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INSPECT TCM POWER SUPPLY CIRCUIT AND SIGNAL CIRCUIT FOR SHORT TO GROUND
• Inspect the applicable circuit for a short to ground.
(See CIRCUIT INSPECTION.)
• Is the circuit normal?
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Yes
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Go to the next step.
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No
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Repair or replace the malfunctioning location and perform the repair completion verification 1.
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13
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INSPECT TCM POWER SUPPLY CIRCUIT AND SIGNAL CIRCUIT FOR OPEN CIRCUIT
• Inspect the applicable circuit for an open circuit.
(See CIRCUIT INSPECTION.)
• Is the circuit normal?
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Yes
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Refer to the controller area network (CAN) malfunction diagnosis flow to inspect for a CAN communication error.
• If the CAN communication is normal, perform the diagnosis from Step 1.
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No
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Repair or replace the malfunctioning location and perform the repair completion verification 1.
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14
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INSPECT RELATED PART CONDITION
• Inspect the following:
• Are all items normal?
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Yes
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Go to the next step.
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No
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Repair or replace the malfunctioning location and perform the repair completion verification 1.
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15
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INSPECT DRIVE BELT FOR MALFUNCTION
• Inspect the applicable part.
• Is the part normal?
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Yes
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Go to the next step.
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No
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Repair or replace the malfunctioning location and perform the repair completion verification 1.
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16
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INSPECT FOR FUEL LEAKAGE FROM FUEL SYSTEM
• Visually inspect the following:
• Are all items normal?
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Yes
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Go to the next step.
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No
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Repair or replace the malfunctioning location and perform the repair completion verification 1.
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17
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INSPECT FUEL INJECTION SYSTEM RELATED PARTS
• Inspect the following parts:
• Are all items normal?
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Yes
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Go to the next step.
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No
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Repair or replace the malfunctioning location and perform the repair completion verification 1.
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18
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INSPECT FOR MALFUNCTION DUE TO POOR FUEL
• Replace the fuel.
• Does the symptom disappear?
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Yes
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Advise the customer as to the change in the fuel used.
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No
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Remove the accumulated matter in the cylinder head using the following procedure, then go to the next step.
• Carbon remover
• Overhauling
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19
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DETERMINE IF MALFUNCTION IS DUE TO EXCESSIVE ENGINE SPEED RESISTANCE
• Rotate the crankshaft pulley lock bolt clockwise using a wrench.
• Can the bolt be rotated?
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Yes
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Go to Step 21.
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No
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Go to the next step.
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20
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INSPECT FOR MALFUNCTION DUE TO EXCESSIVE MECHANICAL RESISTANCE OF ENGINE ACCESSORIES
• Remove all drive belts from engine accessories.
• Start the engine.
• Is cranking possible? (Does engine start?)
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Yes
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Mechanical resistance in engine accessories.
• Repair or replace the malfunctioning location and perform the repair completion verification 1.
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No
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Go to the next step.
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21
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INSPECT ENGINE COMPRESSION
• Inspect the engine compression.
• Are compression pressures within specification?
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Yes
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Perform the repair completion verification 1.
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No
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Go to the next step.
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22
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INSPECT FOR MALFUNCTION DUE TO DEVIATED VALVE TIMING
• Inspect the valve timing (timing chain installation condition).
• Is the valve timing normal?
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Yes
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Go to the next step.
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No
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Adjust the valve timing to the correct timing and perform the repair completion verification 1.
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23
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INSPECT FOR MALFUNCTION DUE TO INTERNAL ENGINE WEAR, DAMAGE
• Inspect for the following engine internal parts:
• Are all items normal?
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Yes
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Refer to the controller area network (CAN) malfunction diagnosis flow to inspect for a CAN communication error.
• If the CAN communication is normal, perform the diagnosis from Step 1.
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No
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Repair or replace the malfunctioning location and perform the repair completion verification 1.
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Repair completion verification 1
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VERIFY THAT VEHICLE IS REPAIRED
• Install/connect the part removed/disconnected during the troubleshooting procedure.
• Has the malfunction symptom been eliminated?
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Yes
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Complete the symptom troubleshooting. (Explain contents of repair to customer)
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No
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Refer to the controller area network (CAN) malfunction diagnosis flow to inspect for a CAN communication error.
• If the CAN communication is normal, perform the diagnosis from Step 1.
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Repair completion verification 2
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VERIFY IF MALFUNCTION IS CAUSED BY NOT PERFORMING PCM REPROGRAMMING
• Verify repair information and verify that there is a new calibration in the PCM.
• Is there a new calibration in the PCM?
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Yes
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Perform the PCM reprogramming and verify if the malfunction symptom was corrected.
• If the malfunction recurs, replace the PCM.
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No
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Replace the PCM.
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