Inspection Procedure 9: When The Cruise Control Switch is Operated, The System is not Turned ON.

OPERATION

This circuit judges the signals of each switches (speed limiter ON/OFF, cruise control ON/OFF, CANCEL, SET - and RES +) of the cruise control switches. The engine-ECU detects the state of the cruise control switches by sensing the voltages shown below.

When all switches are released: 4.7 - 5.0 volts
When the speed limiter ON/OFF switch is pressed: 0 - 0.5 volts
When the cruise control ON/OFF switch is pressed: 0.9 - 1.7 volt
When the CANCEL switch is pressed: 1.9 - 2.7 volts
When the SET - switch is pressed: 2.9 - 3.6 volts
When the RES + switch is pressed: 3.8 - 4.5 volts

COMMENTS ON TROUBLE SYMPTOM

The M.U.T.-III can also be used to check if the circuits of each input switches are normal or not by checking the data list.

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.
Damaged harness or connector.
Malfunction of the cruise control switches.
Malfunction of the clock spring.
Malfunction of the engine-ECU.

DIAGNOSIS PROCEDURE

STEP 1. Check the common rail fuel injection system diagnosis code.

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

Q. Is any diagnosis code set?

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

	Go to Step 2.

STEP 2. Check the data list.

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

Item 136: Cruise main switch.
Item 137: Cruise cancel switch.
Item 138: Cruise set switch.
Item 139: Cruise resume switch.
Item 460: ASLF main switch.

Q. Is the check result normal?

	Go to Step 4.

	Go to Step 3.

STEP 3. Check the cruise control switches.

Refer to

Q. Is the check result normal?

	Go to Step 4.

	Replace the cruise control switches (Refer to ).

STEP 4. Check the symptom.

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

	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 13D - Engine-ECU ).