Inspection Procedure 2: Cruise Control cannot be Set (No Response SET - Switch is Pressed). <4N1>

COMMENTS ON TROUBLE SYMPTOM

The conditions for initiating the adaptive cruise control system (ACC) may not be satisfied.

PROBABLE CAUSES

Malfunction of CAN bus system.
Damaged harness or connector.
Malfunction of the clock spring.
Malfunction of the cruise control switch.
Malfunction of the stop lamp switch.
Malfunction of the inhibitor switch.
Malfunction of the parking brake switch.
Malfunction of the engine system.
Malfunction of the ASC system.
Malfunction of the A/T system.
Malfunction of the ACC/FCM-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 2.

STEP 2. Check whether the diagnosis code is set again.

Q. Is diagnosis code set?

	Repair the adaptive cruise control system (ACC).

	Go to Step 3.

STEP 3. Check the other system diagnosis code.

Using M.U.T.-III, perform diesel fuel system diagnosis code (Refer to GROUP 13D - Troubleshooting, Diagnosis Function

Q. Is any diagnosis code set?

	Repair the diesel fuel system (Refer to GROUP 13D - Troubleshooting, Inspection Chart for Diagnosis Code ).

	Go to Step 4.

STEP 4. Check the other system diagnosis code.

Using M.U.T.-III, perform ASC system diagnosis code (Refer to GROUP 35C - Troubleshooting, Diagnosis Function

Q. Is the diagnosis code set?

	Repair the ASC system (Refer to GROUP 35C - Troubleshooting, Inspection Chart for Diagnosis Code ).

	Go to Step 5.

STEP 5. Check the other system diagnosis code.

Using M.U.T.-III, perform A/T system diagnosis code (Refer to GROUP 23C - Troubleshooting, Diagnosis Function).

Q. Is any diagnosis code set?

	Repair the A/T system (Refer to GROUP 23C -Troubleshooting, Inspection Chart for Diagnosis Code).

	Go to Step 6.

STEP 6. Check the other symptom.

The system should be turned on when the cruise control switch is operated.

Q. Is the system turned on by operating the cruise control switch?

	Go to Step 7.

	Refer to "When the cruise control switch is operated, the system is not turned on."(Refer to )

STEP 7. Check the data list.

Using M.U.T.-III, check the data list of diesel fuel system (Refer to data list reference table

Item 137: Cruise cancel switch.
Item 138: Cruise set switch.

Q. Is the check result normal?

	Go to Step 9.

	Go to Step 8.

STEP 8. Check the cruise control switch.

Q. Is the check result normal?

	Replace the engine-ECU (Refer to GROUP 13D - Engine-ECU ).

	Replace the cruise control switch.

STEP 9. Check the symptom.

(1)Drive the vehicle for approx. three minutes.

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 ACC/FCM-ECU.