INSPECTION PROCEDURE K-1: The seat belt warning lamp does not flash normally. <Vehicles for Australia and New Zealand>


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


COMMENTS ON TROUBLE SYMPTOM
The ETACS-ECU flashes the seat belt warning lamp in accordance with the input signal from the ignition switch (IG1).
If it does not flash normally, these input signal circuit(s) or the ETACS-ECU may be defective.

POSSIBLE CAUSES

  • Malfunction of the ETACS-ECU
  • Damaged harness wires and connectors

DIAGNOSTIC PROCEDURE

Step 1. 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 2.
Refer to Inspection Procedure A-3 "Communication with ETACS-ECU is not possible ."

Step 2. SWS monitor data list.
Check the SWS communication signal, which are related to the seat belt warning buzzer 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 3.
Refer to Inspection Procedure P-2 "The ignition switch (IG1) signal is not received ."

Step 3. Check the seat belt switch, where the seat belt warning lamp does not function normally.

Q. When the seatbelt switch is operated, which seatbelt warning lamp operates normally?
Driver’s seat belt : Go to Step 5.
Passenger’s seat belt : Go to Step 4.

Step 4. ETACS switch data by using the SWS monitor
Check the ETACS-ECU signal related to the seat belt warning buzzer function.

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

Q. Are the check result normal?
Go to Step 6.
Refer to inspection procedure P-17 "The driver’s seat belt switch signal is not received <RH drive vehicles> ."

Step 5. ETACS switch data by using the SWS monitor
Check the ETACS-ECU signal related to the seat belt warning buzzer function.

  • Passenger’s seat belt switch: ON (Unfastened)
  • Seat occupancy sensor: ON (Seat occupied)
Item No.
 Item name
 Normal condition
Item 43
 As.SeatBeltSW
 ON
OK: Normal condition is displayed.

Q. Are the check result normal?
Go to Step 6.
Refer to inspection procedure P-18 "The front passenger’s seat belt switch signal is not received .

Step 6. ETACS ANALOG data by using the SWS monitor.
Check the ETACS-ECU signal related to the seat belt warning buzzer function.

  • Set the simulated vehicle speed at approximately 10km/h.
Item No.
 Item name
 Normal condition
Item 03
 SPEED SENSOR
 8 - 10km/h
OK: Normal condition is displayed.

Q. Is the check result normal?
Go to Step 7.
Refer to inspection procedure P-23 "The vehicle speed signal is not received ."

Step 7. Retest the system.
Check that the seat belt warning lamp work normally.

Q. Is the check result normal?
The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to Cope with Intermittent Malfunction ).
Replace the ETACS-ECU.