INSPECTION PROCEDURE 3: The Tight Corner Braking Phenomenon* Appears with the S-AWC Drive Mode-selector in the AWC ECO or NORMAL Position.


note
  • *Tight corner braking phenomenon: When a 4WD vehicle makes sharp cornering in a paved road at low speed (ex. parallel parking), there is a difference in turning radius between front and rear wheels. If such a difference can no longer be compensated by tyre slippage, the vehicle behaves as if it is under braking.
  • The vehicle is tuned so that the tight corner braking phenomenon appears at a certain level with the drive mode in the SNOW or LOCK position.

COMMENTS ON TROUBLE SYMPTOM


If the tight corner braking phenomenon occurs with the S-AWC drive mode-selector being on the AWC ECO position, the electronic control coupling may have a problem. If the tight corner braking phenomenon occurs only with the S-AWC drive mode-selector being on the NORMAL position, the data received by AWC-ECU from each ECU, the electronic control coupling, or AWC-ECU may have a problem.

PROBABLE CAUSES



DIAGNOSIS PROCEDURE

STEP 1. Check for the tight corner braking phenomenon occurrence during driving on a flat road
(1)Operate the drive-mode selector to switch the drive mode to AWC ECO or NORMAL.
(2)Turn the steering wheel on a flat road clockwise or anti-clockwise 360°or more.
(3)Move the selector lever to D range (1st gear) to start the vehicle slowly.
(4)The vehicle should hesitate to move forwards and a tight corner braking phenomenon should occur.

Q. Does the tight corner braking phenomenon occur?
Go to Step 2.
This diagnosis is complete.

STEP 2. Wiring harness check
(1)Check the wiring harness between the AWC-ECU connector (terminal FSL+, FSL-) and the electronic control coupling solenoid connector (front) for damage or other problem.
(2)Check the wiring harness between the AWC-ECU connector (terminal SOL+, SOL-) and the electronic control coupling solenoid connector (centre) for damage or other problem.
(3)Check the connector(s) or terminal(s) or wiring harness above for damage or other problem.

Q. Is the check result normal?
Go to Step 3.
Repair the connector(s) or terminal(s) or wiring harness.

STEP 3. M.U.T.-III data list
Check the data list for the items below.

  • Item No.8: Steering angle sensor
  • Item No.11: Accelerator position
  • Item No.18: FL wheel speed sensor
  • Item No.19: FR wheel speed sensor
  • Item No.20: RL wheel speed sensor
  • Item No.21: RR wheel speed sensor
  • Item No.22: Yaw rate sensor
  • Item No.23: Lateral G sensor

Q. Is the check result normal?
Go to Step 4.
Perform the troubleshooting of the ASC system (Refer to GROUP 35C - Diagnosis, Diagnostic Trouble Code Chart) or the engine control system (Refer to GROUP 13D - Diagnosis, Diagnostic Trouble Code Chart). Then go to Step 4.

STEP 4. Check for the tight corner braking phenomenon occurrence during driving on a flat road
(1)Execute "Test" (item No. 4 Control OFF) on M.U.T.-III special function.
(2)Operate the drive-mode selector to switch the drive mode to AWC ECO.
(3)Turn the steering wheel on a flat road clockwise or anti-clockwise 360°or more.
(4)Move the selector lever to D range (1st gear) to start the vehicle slowly.
(5)The vehicle should hesitate to move forwards and a tight corner braking phenomenon should occur.
caution The tight corner braking phenomenon will also occur when electronic control coupling (front) fails. When you replace the electronic control coupling (centre), first you should ensure that the electronic control coupling (front) does not fail.

Q. Does the tight corner braking phenomenon occur?
YES (Coil current in the electronic control coupling solenoid is 0 A) : Measure the coil current when the tight corner braking occurs. If the coil current measures 0 A, replace the transfer assembly or electronic control coupling (centre) (Refer to GROUP 27C - Electronic Control Coupling (centre)). Then go to Step 5.
YES (Coil current in the electronic control coupling solenoid is other than 0 A) : Measure the coil current when the tight corner braking occurs. If the coil current is other than 0 A, go to Step 5.
Go to Step 5.

STEP 5. Retest the system.

Q. Does the malfunction occur again?
Replace the AWC-ECU.
The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/How to Cope with Intermittent Malfunctions).