[Previous] [Next]

DTC B2409: STL unit comm.(No response)


caution
  • If the DTC B2409 is set, diagnose the CAN bus lines.
  • Whenever the steering lock unit is replaced, ensure that the communication circuit is normal.






DTC SET CONDITION


When the ignition push switch is pressed, the steering lock unit communicates with KOS-ECU to unlock the IG knob. If the steering lock unit communication error (no response) occurs at this time, the DTC is set.

TECHNICAL DESCRIPTION (COMMENT)


When the IG knob unlock communication is performed by pressing the ignition push switch, if the steering lock unit communication error (no response) occurs, the steering lock unit is judged as abnormal.

TROUBLESHOOTING HINTS



DIAGNOSIS
Required Special Tools:
  • MB991958: Scan Tool (M.U.T.-III Sub Assembly)

    • MB991824: Vehicles Communication Interface (V.C.I.)
    • MB991827: M.U.T.-III USB Cable
    • MB991910: M.U.T.-III Main Harness A (Vehicles with CAN communication system)

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.
(2)Turn the ignition switch to the "ON" position.
(3)Diagnose the CAN bus line.
(4)Turn the ignition switch to the "LOCK" (OFF) position.

Q. Is the CAN bus line found to be normal?

Go to Step 2.

Repair the CAN bus line. (Refer to GROUP 54C - Diagnosis ).

STEP 2. Check key reminder switch connector C-213 and KOS-ECU connector C-31 for loose, corroded or damaged terminals, or terminals pushed back in the connector.

Q. Is the key reminder switch connector C-213 and KOS-ECU connector C-31 in good condition?
Go to Step 3.
Repair the defective connector.

STEP 3. Check the wiring harness between the key reminder switch connector C-213 (terminal No. 12, 9, 11) and the KOS-ECU connector C-31 (terminal No. 4, 5, 31).

  • Check the signal lines for open circuit and short circuit.

Q. Is the wiring harness between key reminder switch connector C-213 (terminal No. 12, 9, 11) and the KOS-ECU connector C-31 (terminal No. 4, 5, 31) in good condition?
Go to Step 4.
The wiring harness may be damaged or the connector(s) may have loose, corroded or damaged terminals, or terminals pushed back in the connector. Repair the wiring harness as necessary.

STEP 4. Replace the key reminder switch, and check whether the diagnostic trouble code is reset.
(1)Erase the DTC.
(2)Turn the ignition switch from the "LOCK" (OFF) position to the "ON" position.
(3)Check if the DTC is set.

Q. Is the DTC set?
Replace KOS-ECU and register the ID codes. (Refer to .)
The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to use Troubleshooting/inspection Service Points - How to Cope with Intermittent Malfunction ).