NO.5 i-stop FUNCTION OPERATES UNDER NO ENGINE-STOP CONDITIONS [SKYACTIV-G 2.5T]

id1103b2001000

5	i-stop FUNCTION OPERATES UNDER NO ENGINE-STOP CONDITIONS
DESCRIPTION	•  i-stop function operates even though system is turned off by pressing i-stop OFF switch. •  i-stop function operates even though vehicle conditions are for non-operation. •  i-stop function operates frequently while parking vehicle.
POSSIBLE CAUSE	i-stop warning light (amber) false illumination •  i-stop warning light (amber) illumination circuit malfunction in instrument cluster •  CAN communication line malfunction between instrument cluster and PCM False detection of i-stop function operation conditions •  False detection of external vehicle temperature within operable range (−10 to 50 °C {14 to 122 °F}) ―  Ambient temperature sensor malfunction (sensor specific malfunction) ―  Short or open circuit in wiring harness between ambient temperature sensor terminal A and PCM terminal 2Q ―  Open circuit in wiring harness between ambient temperature sensor terminal B and PCM terminal 2V •  Climate control unit falsely detects that internal vehicle temperature is within operation range. ―  Cabin temperature sensor malfunction (sensor specific or motor malfunction) ―  Short or open circuit in wiring harness between cabin temperature sensor terminal A and climate control unit terminal 1Q ―  Open circuit in wiring harness between cabin temperature sensor terminal B and climate control unit terminal 1A •  Falsely detects that climate control unit detects that driver-side air mix door is not in MAX COLD position even though driver-side air mix door is in MAX COLD position ―  Driver-side air mix actuator malfunction ―  Driver-side air mix actuator position sensor malfunction ―  Driver-side air mix door or linkage stuck •  False detection of vehicle not being parked ―  False detection of steering wheel rotation speed •  Steering angle sensor initialization malfunction •  EPS control module malfunction •  Falsely detects that vehicle is under safety condition ―  False detection of closed bonnet •  Bonnet latch switch malfunction (stuck closed) •  Short to ground in wiring harness between bonnet latch switch terminal A and rear body control module (RBCM) terminal 3L ―  False detection of closed door, liftgate •  Door latch switch malfunction •  Liftgate latch switch malfunction •  Short to ground in wiring harness between door latch switch and rear body control module (RBCM) •  Open circuit in wiring harness between liftgate latch switch and rear body control module (RBCM) ―  False detection of fastened driver seat belt •  Driver-side buckle switch malfunction •  Open circuit in wiring harness between driver-side buckle switch terminal 5B and SAS control module terminal 2U ―  False detection of inclination angle (false detection of 7 % or less) •  Low-G (XY) sensor (built-into SAS control module) malfunction (In this case, the SAS control module records DTCs C0061:29 and C0062:29.) •  Low-G (XY) sensor (built-into SAS control module) initialization malfunction (In this case, the SAS control module records DTC U2100:00.) ―  False detection of low power brake unit load •  Power brake unit vacuum sensor malfunction •  Short or open circuit in wiring harness between power brake unit vacuum sensor terminal A and PCM terminal 2AF •  Short or open circuit in wiring harness between power brake unit vacuum sensor terminal B and PCM terminal 2AH •  Short or open circuit in wiring harness between power brake unit vacuum sensor terminal C and PCM terminal 2Z

Diagnostic Procedure

STEP	INSPECTION	RESULTS	ACTION
1	VERIFY DTC •  Perform the DTC inspection for the following modules. (See DTC INSPECTION.) ―  PCM ―  TCM ―  Front body control module (FBCM) ―  Rear body control module (RBCM) ―  DSC HU/CM ―  SAS control module ―  Climate control unit •  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 [FRONT BODY CONTROL MODULE (FBCM)].) (See DTC TABLE [REAR BODY CONTROL MODULE (RBCM)].) (See DTC TABLE [DSC HU/CM]) (See DTC TABLE [SAS CONTROL MODULE (STANDARD DEPLOYMENT CONTROL SYSTEM)].) (See DTC TABLE [SAS CONTROL MODULE (TWO-STEP DEPLOYMENT CONTROL SYSTEM)].) (See DTC TABLE [CLIMATE CONTROL UNIT (FULL-AUTO AIR CONDITIONER)].)
		No	Go to the next step.
2*	DETERMINE IF MALFUNCTION CAUSE IS AMBIENT TEMPERATURE SENSOR SIGNAL OR OTHER •  Switch the ignition ON (engine off). •  Compare the ambient temperature sensor on the display with the actual ambient temperature. •  Does the ambient temperature on the display correspond to the actual ambient temperature?	Yes	Go to Step 4.
		No	Go to the next step.
3	INSPECT AMBIENT TEMPERATURE SENSOR •  Inspect the ambient temperature sensor. (See AMBIENT TEMPERATURE SENSOR INSPECTION [FULL-AUTO AIR CONDITIONER].) •  Is there any malfunction?	Yes	Replace the ambient temperature sensor, then go to step 18. (See AMBIENT TEMPERATURE SENSOR REMOVAL/INSTALLATION [FULL-AUTO AIR CONDITIONER].)
		No	Inspect the following: •  Short or open circuit in wiring harness between ambient temperature sensor terminal A and PCM terminal 2Q If there is any malfunction: ―  Refer to the wiring diagram and verify whether or not there is a common connector between ambient temperature sensor terminal A and PCM terminal 2Q. 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 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 or open circuit. •  Open circuit in wiring harness between ambient temperature sensor terminal B and PCM terminal 2V If there is any malfunction: ―  Refer to the wiring diagram and verify whether or not there is a common connector between ambient temperature sensor terminal B and PCM terminal 2V. 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 18.
4*	DETERMINE IF MALFUNCTION CAUSE IS DOOR LATCH SWITCH AND LIFTGATE LATCH SWITCH SIGNAL OR OTHER •  Switch the ignition ON (engine off). •  Access the following rear body control module (RBCM) PIDs using the M-MDS: (See PID/DATA MONITOR INSPECTION.) ―  TRUNK ―  DOOR_D ―  DOOR_ALL •  Are the PID values congruent with the opening and closing of the doors and liftgate? (See PID/DATA MONITOR TABLE [REAR BODY CONTROL MODULE (RBCM)].)	Yes	Go to Step 6.
		No	Go to the next step.
5	INSPECT DOOR LATCH SWITCH AND LIFTGATE LATCH SWITCH •  Inspect the PID-related switch in which the malfunction occurred in Step 4. (See LIFTGATE LATCH AND LOCK ACTUATOR INSPECTION.) (See FRONT DOOR LATCH SWITCH INSPECTION.) (See REAR DOOR LATCH SWITCH INSPECTION.) •  Is there any malfunction?	Yes	Replace the applicable switch, then go to step 18. (See LIFTGATE LATCH AND LOCK ACTUATOR REMOVAL/INSTALLATION.) (See FRONT DOOR LATCH AND LOCK ACTUATOR REMOVAL/INSTALLATION.) (See REAR DOOR LATCH AND LOCK ACTUATOR REMOVAL/INSTALLATION.)
		No	Inspect the following in which the malfunction occurred in Step 4: •  Short to ground in wiring harness between door latch switch and rear body control module (RBCM) If there is any malfunction: ―  Refer to the wiring diagram and verify whether or not there is a common connector between door latch switch and rear body control module (RBCM). 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. •  Open circuit in wiring harness between liftgate latch switch and rear body control module (RBCM) If there is any malfunction: ―  Refer to the wiring diagram and verify whether or not there is a common connector between liftgate latch switch and rear body control module (RBCM). 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 18.
6*	DETERMINE IF MALFUNCTION CAUSE IS DRIVER-SIDE BUCKLE SWITCH SIGNAL OR OTHER •  Switch the ignition ON (engine off). •  Access the SAS control module PID SEAT_B_D using the M-MDS. (See PID/DATA MONITOR INSPECTION.) •  Is the SEAT_B_D PID value congruent with the seat belt condition? (See PID/DATA MONITOR TABLE [SAS CONTROL MODULE (STANDARD DEPLOYMENT CONTROL SYSTEM)].) (See PID/DATA MONITOR TABLE [SAS CONTROL MODULE (TWO-STEP DEPLOYMENT CONTROL SYSTEM)].)	Yes	Go to Step 8.
		No	Go to the next step.
7	INSPECT DRIVER-SIDE BUCKLE SWITCH •  Inspect the driver-side buckle switch. (See BUCKLE SWITCH INSPECTION.) •  Is there any malfunction?	Yes	Replace the driver-side buckle switch, then go to step 18. (See FRONT BUCKLE REMOVAL/INSTALLATION.)
		No	Repair or replace the wiring harness between driver-side buckle switch terminal 5B and SAS control module terminal 2N for a possible open circuit, then go to step 18.
8	DETERMINE IF MALFUNCTION CAUSE IS CABIN TEMPERATURE SENSOR SIGNAL OR OTHER •  Access the climate control unit PID INC_TMP_SEN using the M-MDS. (See PID/DATA MONITOR INSPECTION.) •  Does the INC_TMP_SEN PID value indicate the actual cabin temperature of the vehicle?	Yes	Go to Step 10.
		No	Go to the next step.
9	INSPECT CABIN TEMPERATURE SENSOR •  Inspect the cabin temperature sensor. (See CABIN TEMPERATURE SENSOR INSPECTION [FULL-AUTO AIR CONDITIONER].) •  Is there any malfunction?	Yes	Replace the cabin temperature sensor, then go to step 18. (See CABIN TEMPERATURE SENSOR REMOVAL/INSTALLATION [FULL-AUTO AIR CONDITIONER].)
		No	Inspect the wiring harness between the following terminals for a short or open circuit: •  Cabin temperature sensor terminal A—Climate control unit terminal 1Q •  Cabin temperature sensor terminal B—Climate control unit terminal 1A If there is any malfunction: ―  Refer to the wiring diagram and verify whether or not there is a common connector between the following terminals: •  Cabin temperature sensor terminal A—Climate control unit terminal 1Q •  Cabin temperature sensor terminal B—Climate control unit terminal 1A 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 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 or open circuit. Go to Step 18.
10*	DETERMINE IF MALFUNCTION CAUSE IS BONNET LATCH SWITCH SIGNAL OR OTHER •  Switch the ignition ON (engine off). •  Access the rear body control module (RBCM) PID HOOD using the M-MDS. (See PID/DATA MONITOR INSPECTION.) •  Is the HOOD PID value normal? (See PID/DATA MONITOR TABLE [REAR BODY CONTROL MODULE (RBCM)].)	Yes	Go to Step 12.
		No	Go to the next step.
11	INSPECT BONNET LATCH SWITCH •  Inspect the bonnet latch switch. (See BONNET LATCH SWITCH INSPECTION.) •  Is there any malfunction?	Yes	Replace the bonnet latch switch, then go to step 18. (See BONNET RELEASE LEVER AND RELEASE CABLE REMOVAL/INSTALLATION.)
		No	Repair or replace the wiring harness between bonnet latch switch terminal A and rear body control module (RBCM) terminal 3L for a possible short to ground, then go to step 18.
12	DETERMINE IF MALFUNCTION IS CAUSED BY STEERING ANGLE (ESTIMATED ABSOLUTE ANGLE) SIGNAL ERROR •  Start the engine and idle it. •  Access the EPS control module PID STR_ANG using the M-MDS. (See PID/DATA MONITOR INSPECTION.) •  Is the PID value normal? (See PID/DATA MONITOR TABLE [ELECTRIC POWER STEERING (EPS) CONTROL MODULE].)	Yes	Go to Step 14.
		No	Go to the next step.
13	INSPECT EPS CONTROL MODULE FOR MALFUNCTION •  Inspect the EPS control module. (See EPS CONTROL MODULE INSPECTION.) •  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. (See PID/DATA MONITOR INSPECTION.) (See PID/DATA MONITOR TABLE [ELECTRIC POWER STEERING (EPS) CONTROL MODULE].) •  If the STR_ANG value is normal, go to Step 18. (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 18. (See STEERING WHEEL AND COLUMN REMOVAL/INSTALLATION.)
		No	Replace the EPS control module, then go to Step 18. (See STEERING WHEEL AND COLUMN REMOVAL/INSTALLATION.)
14*	DETERMINE IF MALFUNCTION CAUSE IS POWER BRAKE UNIT VACUUM SENSOR SIGNAL OR OTHER •  Turn off the i-stop system with i-stop OFF switch. •  Start the engine and run it is idling. •  Switch the ignition off. •  Switch the ignition ON (engine off). •  Access the PCM PID BBP using the M-MDS while the brake pedal has been depressed several times. (See PID/DATA MONITOR INSPECTION.) •  Does the monitor value decrease every time the brake pedal is depressed?	Yes	Go to Step 16.
		No	Go to the next step.
15	INSPECT POWER BRAKE UNIT VACUUM SENSOR •  Inspect the power brake unit vacuum sensor. (See POWER BRAKE UNIT VACUUM SENSOR INSPECTION [SKYACTIV-G 2.5T].) •  Is there any malfunction?	Yes	Replace the power brake unit, then go to step 18. (See POWER BRAKE UNIT REMOVAL/INSTALLATION [L.H.D.].) (See POWER BRAKE UNIT REMOVAL/INSTALLATION [R.H.D.].)
		No	Inspect the wiring harness between the following terminals for a short or open circuit: •  Power brake unit vacuum sensor terminal A—PCM terminal 2AF •  Power brake unit vacuum sensor terminal B—PCM terminal 2AH •  Power brake unit vacuum sensor terminal C—PCM terminal 2Z If there is any malfunction: ―  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 2AF •  Power brake unit vacuum sensor terminal B—PCM terminal 2AH •  Power brake unit vacuum sensor terminal C—PCM terminal 2Z 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 or open circuit. •  Repair or replace the malfunctioning part, then go to Step 18. If there is no common connector: •  Repair or replace the wiring harness which has a short or open circuit, then go to Step 18. If there is no malfunction: ―  Go to Step 18.
16	DETERMINE IF MALFUNCTION CAUSE IS DRIVER-SIDE AIR MIX ACTUATOR SIGNAL OR OTHER •  Measure the voltage at the following terminal (wiring harness-side) when the driver-side temperature setting is MAX COLD. ―  Climate control unit terminal 2K (L.H.D.) ―  Climate control unit terminal 2I (R.H.D.) •  Is the voltage normal? (See CLIMATE CONTROL UNIT INSPECTION [FULL-AUTO AIR CONDITIONER].)	Yes	Go to Step 18.
		No	Go to the next step.
17	INSPECT DRIVER-SIDE AIR MIX ACTUATOR •  Inspect the driver-side air mix actuator. (See AIR MIX ACTUATOR INSPECTION [FULL-AUTO AIR CONDITIONER].) •  Is there any malfunction?	Yes	Replace the driver-side air mix actuator, then go to the next step. (See AIR MIX ACTUATOR REMOVAL/INSTALLATION [FULL-AUTO AIR CONDITIONER].)
		No	Inspect the air mix actuator and linkage for sticking. (See A/C UNIT DISASSEMBLY/ASSEMBLY.) •  If there is any malfunction: ―  Repair or replace the malfunctioning part according to the inspection results, then go to the next step.
18	Verify the test results. •  If normal, return to the diagnostic index to service any additional symptoms. (See SYMPTOM DIAGNOSTIC INDEX [SKYACTIV-G 2.5T].) •  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 [SKYACTIV-G 2.5T].)