Inspection Procedure 5
Inspection Procedure 5: Cruise Control cannot be Set (No Response "COAST/SET" Switch and "ACC/RES"
Switch is Pressed.)
COMMENT
- The fail-safe function is probably canceling cruise control system. In this case, checking the cruise control system, MFI system, shift lever system[TC-SST], TC-SST system[TC-SST], ASC system and CAN bus line system DTCs. The scan tool MB991958 can also be used to check if the circuits of each input switch are normal or not by checking the data list.
- In addition, if the option coding data written into the ECM is not normal, the cruise control system does not work.
NOTE:
Press the cruise control switches one by one securely. Otherwise, the cruise control system may not be started.
TROUBLESHOOTING HINTS (THE MOST LIKELY CAUSES FOR THIS CASE:)
- Malfunction of the CAN bus line system.
- ECM option coding data error
- Malfunction of the MFI system.
- Malfunction of the shift lever system[ TC-SST.]
- Malfunction of the TC-SST system[ TC-SST.]
- Malfunction of the ASC system.
- Malfunction of the cruise control switch.
- Malfunction of the stoplight switch.
- Malfunction of the clutch switch[ M/T.]
- Malfunction of the ECM.
DIAGNOSTIC PROCEDURE
Required Special Tools:
- MB991958: Scan Tool (M.U.T.-III Sub Assembly)
- MB991824: V.C.I.
- MB991827: M.U.T.-III USB Cable
- MB991910: M.U.T.-III Main Harness A
CAUTION:
If there is any problem in the CAN bus lines, an incorrect diagnostic trouble code (DTC) may be set. Prior to this diagnosis, diagnose the CAN bus lines Initial Inspection and Diagnostic Overview.)
STEP 1. Using scan tool MB991958, diagnose the CAN bus line.
(1)
CAUTION:
To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991958.
Connect scan tool MB991958 to the data link connector (Refer to Reading and Clearing Diagnostic Trouble Codes.)
(2)Turn the ignition switch to the "ON" position.
(3)Diagnose the CAN bus line (Refer to Scan Tool Testing and Procedures.)
Q. Is the check result satisfactory?
YES Go to Step 2
NO Repair the CAN bus lines CAN Bus Diagnostics Chart). Then go to Step 13.
STEP 2. Using scan tool MB991958, check for ECM option coding data.
(1)Connect scan tool MB991958 to the data link connector (Refer to Reading and Clearing Diagnostic Trouble Codes.)
(2)Turn the ignition switch to the "ON" position.
(3)Check for ECM option coding data Programming and Relearning.)
Q. Is the cruise control item of the ECM option coding data enabled?
YES Go to Step 3.
NO Set the ECM option coding data again. Programming and Relearning.) Then go to Step 13.
STEP 3. Using scan tool MB991958, check for MFI system DTC.
(1)Connect scan tool MB991958 to the data link connector (Refer to Reading and Clearing Diagnostic Trouble Codes.)
(2)Turn the ignition switch to the "ON" position.
(3)Check for MFI system DTC Reading and Clearing Diagnostic Trouble Codes.)
Q. Is any DTC set?
YES Repair the MFI system Multiport Fuel Injection (MFI).) Then go to Step 13.
NO Go to Step 6 [M/T.]
NO Go to Step 4 [TC-SST.]
STEP 4. Using scan tool MB991958, check for shift lever system DTC [TC-SST.]
(1)Connect scan tool MB991958 to the data link connector (Refer to Reading and Clearing Diagnostic Trouble Codes.)
(2)Turn the ignition switch to the "ON" position.
(3)Check for shift lever system DTC Reading and Clearing Diagnostic Trouble Codes.)
Q. Is any DTC set?
YES Repair the shift lever system Shift Lever.) Then go to Step 13.
NO Go to Step 5.
STEP 5. Using scan tool MB991958, check for TC-SST system DTC [TC-SST.]
(1)Connect scan tool MB991958 to the data link connector (Refer to Reading and Clearing Diagnostic Trouble Codes.)
(2)Turn the ignition switch to the "ON" position.
(3)Check for TC-SST system DTC Reading and Clearing Diagnostic Trouble Codes.)
Q. Is any DTC set?
YES Repair the TC-SST system Twin Clutch-Sportronic Shift Transmission (TC-SST).) Then go to Step 13.
NO Go to Step 6.
STEP 6. Using scan tool MB991958, check for ASC system DTC.
(1)Connect scan tool MB991958 to the data link connector (Refer to Reading and Clearing Diagnostic Trouble Codes.)
(2)Turn the ignition switch to the "ON" position.
(3)Check for ASC system DTC Reading and Clearing Diagnostic Trouble Codes.)
Q. Is any DTC set?
YES Repair the ASC system Active Stability Control System (ASC).) Then go to Step 13.
NO Go to Step 7.
STEP 7. Check for cruise control system DTC.
(1)Disconnect the negative (-) battery terminal, to erase the DTC of the cruise control system.
(2)Connect the negative (-) battery terminal.
(3)Turn the ignition switch to the "ON" position, and press the "ON/OFF"
switch to turn the cruise control system to ON (turn on the "CRUISE" indicator light.)
(4)After turning the cruise control system to ON, when 2 minutes or more has elapsed without operating the cruise control switches.
(5)With the cruise control switches not operated, depress the brake pedal for several seconds, and then read the DTC of the cruise control system (Refer to Reading and Clearing Diagnostic Trouble Codes.)
Q. Is any DTC set?
YES Repair the cruise control system (Refer to Cruise Control, Diagnostic Trouble Code Chart.) Then go to Step 13.
NO Go to Step 8.
STEP 8. Using scan tool MB991958, check data list item 75: Cancel switch, item 86: Main switch, item 91: Resume switch and item 92: Set switch.
(1)Connect scan tool MB991958 to the data link connector (Refer to Reading and Clearing Diagnostic Trouble Codes.)
(2)Turn the ignition switch to the "ON" position.
(3)Set scan tool MB991958 to data reading mode for cruise control system (Refer to Scan Tool Testing and Procedures.)
- Item 75: Cancel switch.
- When "CANCEL" switch is at the "ON" position, the display on scan tool MB991958 should be "ON".
- When "CANCEL" switch is at the "OFF" position, the display on scan tool MB991958 should be "OFF".
- Item 86: Main switch.
- When "ON/OFF" switch is at the "ON" position, the display on scan tool MB991958 should be "ON".
- When "ON/OFF" switch is at the "OFF" position, the display on scan tool MB991958 should be "OFF".
- Item 91: Resume switch.
- When "ACC/RES" switch is at the "ON" position, the display on scan tool MB991958 should be "ON".
- When "ACC/RES" switch is at the "OFF" position, the display on scan tool MB991958 should be "OFF".
- Item 92: Set switch.
- When "COAST/SET" switch is at the "ON" position, the display on scan tool MB991958 should be "ON".
- When "COAST/SET" switch is at the "OFF" position, the display on scan tool MB991958 should be "OFF".
Q. Is the switch operating properly?
YES Go to Step 9.
NO Repair the cruise control switch system (Refer to DTC 15, Diagnostic Trouble Code Procedures - DTC 15: Cruise Control Switch System.) Then go to Step 13.
STEP 9. Using scan tool MB991958, check data list item 74: Brake light switch and item 89: Normally closed brake switch.
(1)Connect scan tool MB991958 to the data link connector (Refer to Reading and Clearing Diagnostic Trouble Codes.)
(2)Turn the ignition switch to the "ON" position.
(3)Set scan tool MB991958 to data reading mode for cruise control system (Refer to Scan Tool Testing and Procedures.)
- Item 74: Brake light switch.
- When the brake pedal is depressed, the display on scan tool MB991958 should be "ON".
- When the brake pedal is released, the display on scan tool MB991958 should be "OFF".
- Item 89: Normally closed brake switch.
- When the brake pedal is depressed, the display on scan tool MB991958 should be "ON".
- When the brake pedal is released, the display on scan tool MB991958 should be "OFF".
Q. Is the switch operating properly?
YES Go to Step 10 [M/T.]
YES Go to Step 11 [TC-SST.]
NO Repair the stoplight switch system (Refer to DTC 22, Diagnostic Trouble Code Procedures - DTC 22: Stoplight Switch System.) Then go to Step 13
.
STEP 10. Using scan tool MB991958, check data list item 78: Clutch switch [M/T.]
(1)Connect scan tool MB991958 to the data link connector (Refer to Reading and Clearing Diagnostic Trouble Codes.)
(2)Turn the ignition switch to the "ON" position.
(3)Set scan tool MB991958 to data reading mode for cruise control system (Refer to Scan Tool Testing and Procedures.)
- Item 78: Clutch switch.
- When the clutch pedal is depressed, the display on scan tool MB991958 should be "ON".
- When the clutch pedal is released, the display on scan tool MB991958 should be "OFF".
Q. Is the switch operating properly?
YES Go to Step 12.
NO Repair the clutch switch system (Refer to Inspection Procedure 2, Symptom Procedures - Inspection Procedure 2.) Then go to Step 13.
STEP 11. Using scan tool MB991958, check data list item 88: Neutral switch [TC-SST.]
(1)Connect scan tool MB991958 to the data link connector (Refer to Reading and Clearing Diagnostic Trouble Codes.)
(2)Turn the ignition switch to the "ON" position.
(3)Set scan tool MB991958 to data reading mode for cruise control system (Refer to Scan Tool Testing and Procedures.)
- Item 88: Neutral switch.
- When shift lever is at the "N", "P", "R" position, the display on scan tool MB991958 should be "ON".
- When shift lever is other than "N", "P", "R" position, the display on scan tool MB991958 should be "OFF".
Q. Is the switch operating properly?
YES Go to Step 12.
NO Repair the shift lever system (Refer to Inspection Procedure 4, Symptom Procedures - Inspection Procedure 3.) Then go to Step 13.
STEP 12. Check the symptom.
Q. Can cruise control be set?
YES It can be assumed that this malfunction is intermittent How to Cope With Intermittent Malfunctions.)
NO Replace the ECM [ Removal and Replacement.] Then go to Step 13.
STEP 13. Check the symptom.
Q. Can cruise control be set?
YES The procedure is complete.
NO Return to Step 1.