[ Model - ECLIPSE CROSS / Year - 2018 ]
2018 / ECLIPSE CROSS / EC - Workshop Manual
35 -SERVICE BRAKES > 35C-ACTIVE STABILITY CONTROL SYSTEM (ASC) > TROUBLESHOOTING<ASC-ECU><ASC-ECU> > SYMPTOM PROCEDURES > HSA DOES NOT WORK.
Inspection Procedure 14: HSA (Hill Start Assist) does not work.
 
 
caution
  • If there is any problem in the CAN bus lines, an incorrect diagnosis code may be set. Prior to this diagnosis, diagnose the CAN bus lines (Refer to GROUP 54C - CAN Bus Diagnostics Table ).
  • Whenever ECU is replaced, ensure that the CAN bus lines are normal.
 
 
COMMENTS ON TROUBLE SYMPTOM
  • The slope gradient may be low.
  • The vehicle is not completely stationary.
  • A failure may have occurred in the calibration of the G and yaw rate sensor or brake fluid pressure sensor.
  • A defective parking brake may cause the HSA not to function.
  • A problem (noise interference) may have occurred in the CAN bus line, resulting in an improper communication with ASC-ECU or each ECU.
note
  • The HSA does not work even when the wheel speed sensor output pulse (vehicle moved) while the vehicle is parked.
  • The HSA is affected by the loading conditions and vehicle posture at the occurrence of phenomenon. When checking the HSA operation in actual driving, carry out the check on the vehicle with one occupant (driver) only.
 
 
 
PROBABLE CAUSES
  • Calibration failure of the G and yaw rate sensor
  • Calibration failure of the brake fluid pressure sensor
  • Malfunction of parking brake
  • Malfunction of wheel speed sensor
  • Malfunction of ETACS-ECU
  • Malfunction of hydraulic unit (integrated with ASC-ECU)
  • Wiring harness or connector failure of CAN bus line
  • Damaged wiring harness and connectors
 
 
 
 
DIAGNOSIS PROCEDURE
STEP 1. HSA operation check
Check if the HSA works with one occupant (driver) only in the vehicle.
Is the check result normal?
This diagnosis is complete.
Go to Step 2.
 
STEP 2. Parking brake check
Does the brake warning lamp remain on after the parking brake is released?
Is the check result normal?
Go to Step 3.
Carry out Inspection procedure 3 "The brake warning lamp does not go out (ABS warning lamp is OFF) although the parking brake is released" (Refer to ).
 
STEP 3. M.U.T.-IIISE CAN bus diagnostics
Use M.U.T.-IIISE to diagnose the CAN bus lines.
Is the check result normal?
Go to Step 4.
Repair the CAN bus lines (Refer to GROUP 54C - CAN Bus Diagnostics Table ).
 
STEP 4. M.U.T.-IIISE diagnosis code
Use M.U.T.-IIISE to check the diagnosis code for the ASC system.
Is the diagnosis code set?
Carry out the diagnosis for the diagnosis code (Refer to ).
Go to Step 5.
 
STEP 5. M.U.T.-IIISE data list
Check the following data list (Refer to ).
  • Apply the parking brake.
 
Item No.Item nameNormal condition
29Parking brake switchON
  • Release the parking brake.
 
Item No.Item nameNormal condition
29Parking brake switchfrom "ON" to "OFF"
  • The selector lever is in the "R", "D", "N" and "P" position. <Except M/T>
 
Item No.Item nameNormal condition
15Target gear
  • "R"
    • Selector lever: "R" position
  • "D"
    • Selector lever: "D" position
  • "P"
    • Selector lever: "P" position
  • "N"
    • Selector lever: "N" position
14Actual gear
Is the check result normal?
Go to Step 6.
NO <Item No.29> : Carry out the Inspection procedure 3 "The brake warning lamp does not go out (ABS warning lamp is OFF) although the parking brake is released" (Refer to ).
NO <Item No.14, 15> : Go to Step 9.
 
STEP 6. M.U.T.-IIISE data list
Check the following data list under curb weight condition or one occupant (driver) only in the vehicle, on a flat road.(Refer to )
  • Item 06: Yaw rate sensor
  • Item 09: G sensor
Is the check result normal?
Go to Step 7.
Carry out the calibration of the G and yaw rate sensor (Refer to ). Then go to Step 9.
 
STEP 7. M.U.T.-IIISE data list
Check the following data list (Refer to ).
  • Item 07: Master cylinder pressure
Is the check result normal?
Go to Step 8.
Carry out the calibration of the brake fluid pressure sensor (Refer to ).
 
STEP 8. M.U.T.-IIISE diagnosis code
Use M.U.T.-IIISE to check that the diagnosis code is set in the CVT-ECU.
Is the diagnosis code set?
Carry out the diagnosis for the diagnosis code (Refer to GROUP - 23A - Troubleshooting/Diagnosis Code Chart ).
Go to Step 9.
 
STEP 9. Retest the system.
Check if the HSA works with one occupant (driver) only in the vehicle.
Is the check result normal?
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/How to Cope with Intermittent Malfunctions ).
Replace the hydraulic unit (integrated with ASC-ECU) (Refer to ).