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, TC-SST system, shift lever 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 TC-SST system [TC-SST.]
- Malfunction of the shift lever system [TC-SST.]
- Malfunction of the cruise control switch.
- Malfunction of the stoplight switch.
- Malfunction of the clutch switch [M/T.]
- Malfunction of the TC-SST-ECU [TC-SST.]
- Malfunction of the shift lever ECU [TC-SST.]
- 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.

STEP 1. Using scan tool MB991958, diagnose the CAN bus line.

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.







1. Connect scan tool MB991958 to the data link connector.
2. Turn the ignition switch to the "ON" position.
3. Diagnose the CAN bus line.

Q: Is the check result satisfactory?

YES : Go to Step 2

NO : Repair the CAN bus lines. Then go to Step 12.

STEP 2. Using scan tool MB991958, check for ECM option coding data.

1. Connect scan tool MB991958 to the data link connector.
2. Turn the ignition switch to the "ON" position.
3. Check for ECM option coding data.

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. Then go to Step 12.

STEP 3. Using scan tool MB991958, check for MFI system DTC.

1. Connect scan tool MB991958 to the data link connector.
2. Turn the ignition switch to the "ON" position.
3. Check for MFI system DTC.

Q: Is any DTC set?

YES : Repair the MFI system. Then go to Step 12.

NO : Go to Step 6 [M/T.]

NO : Go to Step 4 [TC-SST.]

STEP 4. Using scan tool MB991958, check for TC-SST system DTC [TC-SST.]

1. Connect scan tool MB991958 to the data link connector.
2. Turn the ignition switch to the "ON" position.
3. Check for TC-SST system DTC.

Q: Is any DTC set?

YES : Repair the TC-SST system. Then go to Step 12.

NO : Go to Step 5.

STEP 5. Using scan tool MB991958, check for shift lever system DTC [TC-SST.]

1. Connect scan tool MB991958 to the data link connector.
2. Turn the ignition switch to the "ON" position.
3. Check for shift lever system DTC.

Q: Is any DTC set?

YES : Repair the shift lever system. Then go to Step 12.

NO : Go to Step 6.

STEP 6. 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.

Q: Is any DTC set?

YES : Repair the cruise control system. Then go to Step 12.

NO : Go to Step 7.

STEP 7. 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.
2. Turn the ignition switch to the "ON" position.
3. Set scan tool MB991958 to data reading mode for cruise control system.
- 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 8.

NO : Repair the cruise control switch system. Then go to Step 12.

STEP 8. 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.
2. Turn the ignition switch to the "ON" position.
3. Set scan tool MB991958 to data reading mode for cruise control system.
- 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 9 [M/T.]

YES : Go to Step 10 [TC-SST.]

NO : Repair the stoplight switch system. Then go to Step 12.

STEP 9. Using scan tool MB991958, check data list item 78: Clutch switch [M/T.]

1. Connect scan tool MB991958 to the data link connector.
2. Turn the ignition switch to the "ON" position.
3. Set scan tool MB991958 to data reading mode for cruise control system.
- 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 11.

NO : Repair the clutch switch system. Then go to Step 12.

STEP 10. Using scan tool MB991958, check data list item 88: Neutral switch [TC-SST.]

1. Connect scan tool MB991958 to the data link connector
2. Turn the ignition switch to the "ON" position.
3. Set scan tool MB991958 to data reading mode for cruise control system.
- 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 11.

NO : Repair the shift lever system. Then go to Step 12.

STEP 11. Check the symptoms.

Q: Can cruise control be set?

YES : It can be assumed that this malfunction is intermittent.

NO : Replace the ECM. When the ECM is replaced, register the encrypted code. Then go to Step 12.

STEP 12. Check the symptoms.

Q: Can cruise control be set?

YES : The procedure is complete.

NO : Return to Step 1.