4.
Monitor the "steering sensor" parameters on the Scantool.
The Steering angle sensor(SAS) is composed of main gear, serve gear1 and serve gear2 to determine the turning direction. The SAS is a CAN communication type sensor. If main gear is rotated according to the rotation of steering wheel serve gear1 and serve gear2, which is contact with main gear, will be rotated. The HECU detects the absolute angle by using magnetic MR effect and the difference gear ratio of each serve gear and then send to the CAN comunication line. The HECU detects the steering wheel's operating speed and operating angle by using absolute angle, and this signal is used in a input signal of anti-roll control.
The SAS used for ESP control needs zero point adjustment because the SAS measures a absolute angle. zero point adjustment is done by using the scantool device. If abnormal zero point adjustment is detected, a failure is reconized.
Item | Detecting Condition | Possible cause |
DTC Strategy | ● Signal Monitoring | ● A fail of SAS zero point adjustment ● Faulty HECU |
Monitoring Period | ● During SAS zero point adjustment. | |
Enable Conditions | ● The position of steering wheel is out of specified range (straight positon, a max. error ±5°) during SAS zero point adjustment. | |
Fail Safe | ● Reduced controller function caused by faulty SAS signal. Allow the ABS/EBD control. ● The ESP warning lamp is activated. |
Connect scantool to Data Link Connector(DLC).
Ignition "ON" ＆ Engine "ON".
Turn the steering wheel to the left or right until can't turn the steering wheel any more.
Monitor the "steering sensor" parameters on the Scantool.
Is parameter displayed within specifications?
▶ Fault is caused by having been repaired and HECU memory was not cleared. Clear the DTC and then go to "Verification of Vehicle Repair" procedure.
▶ Go to "Component Inspection" procedure.
Line up wheels like (figure 1).
Perform the wheel alignment.
Line up the steering wheel in a straight.
Go ahead and Go back the vehicle 2~3 times without holding steering wheel.
Connect scantool to Data Link Connector(DLC).
Go in Anti-Rock brake system. (figure 2).
Perform steering angle sensor calibration. (figure 3).
Disconnect scantool.
Check the condition of SAS zero point adjustment by opreating the vehicle (turn right and left at least 1 time)
Is zero point adjustment completed?
▶ Go to "Verification of Vehicle Repair" procedure.
▶ Substitute with a known-good HECU and check for proper operation. If problem is corrected, replace HECU and then go to "Verification of Vehicle Repair" procedure.
After a repair, it is essential to verify that the fault has been corrected.
Connect scantool and select "Diagnostic Trouble Codes(DTCs)" mode
Using a scantool, Clear DTC.
Operate the vehicle within DTC Detecting Condition in General Information.
Are any DTCs present ?
▶ Go to the applicable troubleshooting procedure.
▶ System performing to specification at this time.
