Inspection Procedure B-4: Seat belt reminder function does not work normally.


caution Whenever the ECU is replaced, ensure that the input and output signal circuits are normal.

COMMENTS ON TROUBLE SYMPTOM
If the seat belt reminder function does not work normally, the input signal circuits below or the ETACS-ECU may be defective.

  • Ignition switch (IG1)
  • Driver’s seat belt switch
  • Speed signal

PROBABLE CAUSES

  • Malfunction of the CAN bus line
  • Malfunction of the combination meter
  • Malfunction of the ETACS-ECU
  • Malfunction of the driver’s seat belt switch
  • Damaged harness wires and connectors

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III CAN bus diagnostics
Use the M.U.T.-III to diagnose the CAN bus lines.

Q. Is the check result normal?
Go to Step 2.
Repair the CAN bus line (Refer to GROUP 54D - Troubleshooting ).

STEP 2. M.U.T.-III other system diagnosis code
Check if an combination meter diagnosis code is set.

Q. Is the diagnosis code set?
Diagnose the combination meter (Refer to ).
Go to Step 3.

STEP 3. M.U.T.-III diagnosis code
Check if an ETACS-ECU diagnosis code is set.

Q. Is the diagnosis code set?
Refer to diagnosis code chart .
Go to Step 4.

STEP 4. ECU check by using the SWS monitor
Check that the power supply and earth lines to the ETACS-ECU and the SWS communication lines are normal.

  • Turn the ignition switch to the ON position.
ECU TO BE CHECKED
  • ETACS ECU
OK: "OK" is displayed on the "ETACS ECU" menu.

Q. Is the check result normal?
Go to Step 5.
Refer to GROUP 54C - Inspection Procedure 2 "Communication with the ETACS-ECU is not possible ."

STEP 5. SWS monitor data list.
Check the SWS communication signal, which are related to the seat belt reminder function.
Selected item ETACS ECU
  • Ignition switch: ON
Item No.
 Item name
 Normal condition
Item 30
 IG SW(IG1)
 ON
OK: Normal condition is displayed.

Q. Is the check result normal?
Go to Step 6.
Refer to .

STEP 6. ETACS switch data by using the SWS monitor
Check the ETACS-ECU signal related to the seat belt reminder function.

  • Driver’s seat belt switch: ON (Unfastened)
Item No.
 Item name
 Normal condition
Item 12
 Driver’s seat belt switch
 ON
OK: Normal condition is displayed.

Q. Are the check result normal?
Go to Step 7.
Refer to .

STEP 7. Check the combination meter.
Check that the speedometer works normally.

Q. Is the check result normal?
Go to Step 8.
Diagnose the combination meter (Refer to ).

STEP 8. Retest the system.
Check that the seat belt reminder function work normally.

Q. Is the check result normal?
The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to use troubleshooting/Inspection Service Points ).
Replace the ETACS-ECU.