Inspection procedure 14: The Seat Belt Warning Lamp does not Illuminate or flash.


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


COMMENTS ON TROUBLE SYMPTOM


The ETACS-ECU operates this function in accordance with the input signals below.

If this function does not work normally, these input signal circuit(s) or the ETACS-ECU may be defective.

PROBABLE CAUSES



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 54C - Troubleshooting ). On completion, go to Step 5.

STEP 2. Check the diagnosis code of the engine-ECU.
Check if the diagnosis code is set in either of the engine-ECU.

Q. Is the diagnosis code set?
Diagnose the engine-ECU (Refer to GROUP 13A - Troubleshooting . On completion, go to Step 4.
Go to Step 3.

STEP 3. M.U.T.-III data list
Check the input signals below, which are related to the seat belt warning lamp function.

  • Turn the ignition switch to the "ON" position.
  • Remove the each inserted seatbelt.
Item No.
 Item name
 Normal condition
30
 Ignition switch(IG1)
 ON
50
 Driver’s seatbelt(Buckle SW)
 Being turned ON from OFF
51
 Passenger seatbelt(Buckle SW)
OK: Normal conditions are displayed for all the items.

Q. Is the check result normal?
YES <All the signals are received normally.> : Go to Step 4.
NO <The seat belt switch signal is not received.> : Refer to inspection procedure C-6 "The shet belt switch signal is not recived <L.H. drive vehicles> or <R.H. drive vehicles>."
NO <The ignition switch (IG1) signal is not received.> : Refer to inspection procedure C-3 "The ignition switch (IG1) signal is not received ."

STEP 4. Check the combination meter

Q. Does the combination meter work?
Go to Step 5.
Refer to symptom procedure 1 "Power supply circuit systm check ."

STEP 5. Connector check: C-113 combination meter connector and C-219 ETACS-ECU connector




Q. Is the check result normal?

Go to Step 6.

Repair the defective connector.

STEP 6. Check the wiring harness from C-113 combination meter connector terminal No.2 to C-219 ETACS-ECU connector terminal No.55.





  • Check the output lines for open circuit.

Q. Is the check result normal?

Go to Step 7.

Repair the wiring harness.

STEP 7. Retest the system.
The door-ajar warning lamp function should 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 - How to Cope with Intermittent Malfunction ).
Replace the ETACS-ECU.