Inspection Procedure 4: Cruise Control cannot be Set (No Response when the "COAST/SET" Switch and the "ACC/RES" Switch is Pressed).


COMMENTS ON TROUBLE SYMPTOM



note Press the cruise control switches one by one securely. Otherwise, the cruise control system may not be started.

PROBABLE CAUSES



  • Malfunction of CAN bus system.
  • Malfunction of the diesel fuel system.
  • Malfunction of the cruise control switch.
  • Malfunction of the stop lamp switch.
  • Malfunction of the clutch switch.
  • Malfunction of the engine-ECU.

DIAGNOSIS PROCEDURE
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.
  • Before replacing the ECU, ensure that the CAN bus lines is normal.

STEP 1. Check the CAN bus system diagnosis.
Using M.U.T.-III, perform CAN bus diagnosis (Refer to GROUP 54C - Explanation About The M.U.T-III Can Bus Diagnostics ).

Q. Is the check result satisfactory?
Go to Step 2.
Repair the CAN bus lines (Refer to GROUP 54C - Troubleshooting, Can Bus Diagnostic Table ). Then go to Step 8.

STEP 2. Check the diesel fuel system diagnosis code.
Using M.U.T.-III, perform diesel fuel system diagnosis code (Refer to GROUP 13A - Diagnosis Function ).

Q. Is any diagnosis code set?
Repair the diesel fuel system (Refer to GROUP 13A - Troubleshooting, Inspection Chart for Diagnosis Trouble Code ). Then go to Step 8.
Go to Step 3.

STEP 3. Check the diagnosis code.
Using M.U.T.-III, read the diagnosis code of the cruise control system (Refer to ).

Q. Is any diagnosis code set?
Repair the cruise control system (Refer to - Diagnosis Code Chart) <BSY>. Then go to Step 8.
Go to Step 4.

STEP 4. Check the data list.
Using M.U.T.-III, check the data list.

  • Item 285: Cruise control switch
(Refer to data list reference table ) <BSY>.

Q. Is the check result normal?
Go to Step 5.
Refer to - Diagnosis Code Procedures, Code No. P0578: Cruise control switch stuck. Then go to Step 8.

STEP 5. Check the data list.
Using M.U.T.-III, check the data list.

  • Item 74: Stop lamp switch
  • Item 89: Brake switch
(Refer to data list reference table ) <BSY>.

Q. Is the check result normal?
Go to Step 6.
Refer to - Diagnosis Code Procedures, Code No. P0504: Brake switch correction. Then go to Step 8.

STEP 6. Check the data list.
Using M.U.T.-III, check the data list.

  • Item 608: Clutch switch
(Refer to data list reference table ) <BSY>.

Q. Is the check result normal?
Go to Step 7.
Refer to - Diagnosis Code Procedures, Code No. P0830: Clutch switch circuit. Then go to Step 8.

STEP 7. Check the symptoms.

Q. Can cruise control be set?
It can be assumed that this malfunction is intermittent (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points, How to Cope with Intermittent Malfunction ).
Replace the engine-ECU (Refer to GROUP 13A - Engine-ECU ). Then go to Step 8.

STEP 8. Check the symptoms.

Q. Can cruise control be set?
The procedure is complete.
Return to Step 1.