Inspection Procedure 3
INSPECTION PROCEDURE 3: When the Shift Lever is Moved to "N" Position, Cruise Control System is not CancelledCIRCUIT OPERATION
When the shift lever is in the "N" position, the signal is transmitted from the shift lever ECU to the ECM via CAN bus line.
COMMENT
- Malfunction of CAN bus line.
- Malfunction of shift lever system.
TROUBLESHOOTING HINTS (THE MOST LIKELY CAUSES FOR THIS CASE:)
- Malfunction of CAN bus system.
- Damaged harness or connector.
- Malfunction of the shift lever system.
- Malfunction of the shift lever ECU.
- Malfunction of the ECM.
DIAGNOSIS
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 DTC may be set. Prior to this diagnosis, diagnose the CAN bus lines.
- Whenever the ECM is replaced, ensure that the CAN bus lines are normal.
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. Scan Tool Connecting
2. Turn the ignition switch to the "ON" position.
3. Diagnose the CAN bus line. How to Diagnose the CAN Bus Line
4. Turn the ignition switch to the "LOCK" (OFF) position.
5. Disconnect scan tool MB991958.
Q: Is the check result satisfactory?
YES : Go to Step 2
NO : Repair the CAN bus lines (Refer to Controller Area Network, Diagnosis Can Bus Diagnostic Chart). Then go to Step 6.
STEP 2. Using scan tool MB991958, check the shift lever system data list item 01: Shift lever position.
1. Connect scan tool MB991958 to the data link connector. Scan Tool Connecting
2. Turn the ignition switch to the "ON" position.
3. Set scan tool MB991958 to data reading mode for shift lever system (Refer to Twin Clutch-Sportronic Shift Transmission (TC-SST), Diagnosis
- Item 1: Shift lever position.
4. Turn the ignition switch to the "LOCK" (OFF) position.
5. Disconnect scan tool MB991958.
Q: Is the switch operating properly?
YES : Go to Step 3.
NO : Diagnose the shift lever system (Refer to Twin Clutch-Sportronic Shift Transmission (TC-SST), Diagnosis
STEP 3. Using scan tool MB991958, read the shift lever system diagnostic trouble code.
1. Connect scan tool MB991958 to the data link connector. Scan Tool Connecting
2. Turn the ignition switch to the "ON" position.
3. Check for shift lever system diagnostic trouble code (Refer to Twin Clutch-Sportronic Shift Transmission (TC-SST), Diagnosis
4. Turn the ignition switch to the "LOCK" (OFF) position.
5. Disconnect scan tool MB991958.
Q: Is any DTC set?
YES : Diagnose the shift lever system (Refer to Twin Clutch-Sportronic Shift Transmission (TC-SST), Diagnosis
NO : Go to Step 4.
STEP 4. Using scan tool MB991958, check data list item 87: Neutral switch.
1. Connect scan tool MB991958 to the data link connector. Scan Tool Connecting
2. Turn the ignition switch to the "ON" position.
3. Set scan tool MB991958 to data reading mode for cruise control system. Reading Diagnostic Trouble Codes
- Item 87: Neutral switch.
- When shift lever is at the "N" or "P" position, the display on scan tool MB991958 should be "ON".
- When shift lever is other than "N" or "P" position, the display on scan tool MB991958 should be "OFF".
4. Turn the ignition switch to the "LOCK" (OFF) position.
5. Disconnect scan tool MB991958.
Q: Is the switch operating properly?
YES : Go to Step 5.
NO : Replace the ECM [Refer to MFI, Engine Control Module (ECM)]. When the ECM is replaced, register the encrypted code (Refer to Wireless Control Module, Diagnosis-ID Code Registration Judgment Table). Then go to Step 6.
STEP 5. Check the symptoms.
Q: When the shift lever is moved to "N" position, cruise control system is cancelled?
YES : It can be assumed that this malfunction is intermittent (Refer to General (Body and Chassis), How to Use Troubleshooting/Inspection Service Points-How to Cope with Intermittent Malfunction).
NO : Replace the ECM [Refer to MFI, Engine Control Module (ECM)]. When the ECM is replaced, register the encrypted code (Refer to Wireless Control Module, Diagnosis-ID Code Registration Judgment Table). Then go to Step 6.
STEP 6. Check the symptoms.
Q: When the shift lever is moved to "N" position, cruise control system is cancelled?
YES : The procedure is complete.
NO : Return to Step 1.