NO.7 LIMITED i-stop FUNCTION OPERATION TIME [SKYACTIV-G 2.5T]

id1103b2001200

7

LIMITED i-stop FUNCTION OPERATION TIME
DESCRIPTION
•  Frequency of which i-stop function operates is low.
•  Frequent occurrence of engine restarting other than for driving vehicle from stop.
POSSIBLE CAUSE
Note
•  To ensure electric vehicle system reliability, restart the engine regardless of the vehicle condition after 120 s have elapsed since the i-stop function operated.
Battery voltage low during i-stop function operation
•  Battery deterioration
•  Insufficient battery recharge while engine is running
?  Low recharge effect
•  Generator malfunction (part, system, control malfunction)
•  Large amount of vehicle power consumption
•  High electrical load from aftermarket electrical accessories
False detection of engine starting conditions
•  False detection of battery voltage
•  False detection of low power brake unit vacuum sensor load
?  Power brake unit vacuum sensor malfunction
?  Short or open circuit in wiring harness between the following terminals:
•  Power brake unit vacuum sensor terminal A—PCM terminal 2Z
•  Power brake unit vacuum sensor terminal C—PCM terminal 2AF
•  Power brake unit vacuum sensor terminal B—PCM terminal 2AH
?  Power brake unit malfunction (air tightness malfunction)
?  Malfunction in vacuum hose to power brake unit (damage, bad check valve)
False recognition of driver performing engine start operation
•  False detection of released brake pedal
?  Brake fluid pressure sensor (built-into DSC HU/CM) malfunction
•  False detection of steering wheel operation
?  Steering angle sensor initialization malfunction
?  EPS control module malfunction
•  When performing an asterisked (*) troubleshooting inspection, shake the wiring harness and connectors while performing the inspection to discover whether poor contact points are the cause of any intermittent malfunctions.If there is a problem, check to make sure connectors, terminals and wiring harnesses are connected correctly and undamaged.

Diagnostic Procedure

STEP

INSPECTION

RESULTS

ACTION
1
INSPECT EFFECT OF NON-GENUINE ELECTRICAL ACCESSORY FOR CAUSE OF MALFUNCTION
•  Remove any non-genuine electrical accessory.
•  Verify the malfunction symptom.
•  Is the frequency of the engine restarting from the i-stop off condition the same as that of another vehicle of the same model?
Yes
The system is normal.
•  Explain to the customer that the frequency of the engine restarting increases due to the effect of the non-genuine electrical accessory installed.
No
Go to the next step.
2
VERIFY DTC
•  Retrieve the PCM, TCM, rear body control module (RBCM), DSC HU/CM, instrument cluster and climate control unit DTCs using the M-MDS.
•  Are any DTCs present?
Yes
Go to the applicable DTC inspection.
(See DTC TABLE [PCM (SKYACTIV-G 2.5T)].)
(See ON-BOARD DIAGNOSTIC SYSTEM DTC TABLE [TCM (GW6A-EL, GW6AX-EL)])
(See DTC TABLE [REAR BODY CONTROL MODULE (RBCM)].)
(See DTC TABLE [DSC HU/CM])
(See DTC TABLE [INSTRUMENT CLUSTER].)
(See DTC TABLE [CLIMATE CONTROL UNIT (FULL-AUTO AIR CONDITIONER)].)
No
Go to the next step.
3
VERIFY BATTERY CONDITION
•  Inspect the battery.
•  Is there any malfunction?
Yes
Go to the next step.
No
Go to Step 5.
4
DETERMINE IF MALFUNCTION CAUSE IS BATTERY OR GENERATOR
•  Recharge the battery.
•  Inspect the battery again.
•  Is there any malfunction?
Yes
Replace the battery, then go to step 13.
(See BATTERY REMOVAL/INSTALLATION.)
No
Go to the next step.
5
INSPECT GENERATOR
•  Inspect the generator.
•  Is there any malfunction?
Yes
Repair or replace the malfunctioning part according to the inspection results, then go to step 13.
No
Go to the next step.
6
DETERMINE IF MALFUNCTION CAUSE IS STEERING ANGLE SENSOR SIGNAL OR OTHER
•  Start the engine and let it idle.
•  Access the EPS control module PID STR_ANG using the M-MDS.
•  Is the PID value normal?
Yes
Go to Step 8.
No
Go to the next step.
7
INSPECT EPS CONTROL MODULE FOR MALFUNCTION
•  Inspect the EPS control module.
•  Is the EPS control module normal?
Yes
Perform the following procedure:
1.  Switch the ignition off, and after 2 min or more have elapsed, switch the ignition ON.
2.  Start the engine and drive the vehicle 10 m {33 ft} or more in a straight line at a speed of 10 km/h {6.2 mph} or more.
3.  Stop the vehicle with the wheels in the straight-ahead position.
4.  Access the EPS control module PID STR_ANG using the M-MDS.
•  If the STR_ANG value is normal, go to step 13. (Because the steering angle (estimated absolute angle) has returned to normal)
•  If the STR_ANG value is not normal, replace the EPS control module, then go to step 13.
No
Replace the EPS control module, then go to step 13.
(See STEERING WHEEL AND COLUMN REMOVAL/INSTALLATION.)
8
DETERMINE IF MALFUNCTION CAUSE IS POWER BRAKE UNIT VACUUM SENSOR SIGNAL OR OTHER
•  Put the vehicle in an i-stop condition (engine stopped).
•  Access the PCM PID BBP using the M-MDS with the brake pedal depressed and the engine stopped.
•  Does the BBP PID value remain less than ?47.8 kPa {?0.487 kgf/cm2, ?6.93 psi}?
Yes
Go to Step 12.
No
Go to the next step.
9
INSPECT POWER BRAKE UNIT FOR AIR TIGHTNESS MALFUNCTION
•  Perform the vacuum function inspection for the power brake unit and the vacuum loss inspection.
•  Is there any malfunction?
Yes
Repair or replace the malfunctioning part according to the inspection results, then go to step 13.
No
Go to the next step.
10
INSPECT POWER BRAKE UNIT VACUUM SENSOR
•  Inspect the power brake unit vacuum sensor.
•  Is there any malfunction?
Yes
Replace the power brake unit, then go to step 13.
(See POWER BRAKE UNIT REMOVAL/INSTALLATION [L.H.D.].)
(See POWER BRAKE UNIT REMOVAL/INSTALLATION [R.H.D.].)
No
Go to the next step.
11
INSPECT POWER BRAKE UNIT VACUUM SENSOR CIRCUIT FOR SHORT TO GROUND OR OPEN CIRCUIT
•  Inspect for open or short circuit between the following terminals (wiring harness-side):
?  Power brake unit vacuum sensor terminal A—PCM terminal 2Z
?  Power brake unit vacuum sensor terminal C—PCM terminal 2AF
?  Power brake unit vacuum sensor terminal B—PCM terminal 2AH
•  Is there any malfunction?
Yes
Refer to the wiring diagram and verify whether or not there is a common connector between the following terminals:
•  Power brake unit vacuum sensor terminal A—PCM terminal 2Z
•  Power brake unit vacuum sensor terminal C—PCM terminal 2AF
•  Power brake unit vacuum sensor terminal B—PCM terminal 2AH
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 or open circuit.
•  Repair or replace the malfunctioning part.
If there is no common connector:
•  Repair or replace the wiring harness which has a short to ground or open circuit.
Go to step 13.
No
Replace the PCM, then go to step 13.
(See PCM REMOVAL/INSTALLATION [SKYACTIV-G 2.5T].)
12
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 BFP using the M-MDS while the brake is depressed and held with the i-stop function operating.
•  Does the monitoring value change?
Yes
Repeat the inspection from step 1.
•  If the malfunction is not resolved, replace the PCM.
Go to the next step.
No
Brake fluid pressure sensor malfunction, then go to the next step.
•  Replace the DSC HU/CM.
13
Verify the test results.
•  If normal, return to the diagnostic index to service any additional symptoms.
•  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.