Inspection Procedure 2: The Room Lamp does not Illuminate Normally. <Not Using SWS Monitor>


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


















COMMENTS ON TROUBLE SYMPTOM
If the room lamp does not illuminate or extinguish normally, wiring harness connector(s) or the bulb may be defective.

PROBABLE CAUSES

  • Malfunction of the interior lamp switches
  • Malfunction of the room lamp bulbs
  • Malfunction of the rear personal lamp bulbs
  • Damaged harness wires and connectors

DIAGNOSIS PROCEDURE

STEP 1. Pulse check
Check the input signals below, which are related to the room lamp.
System switch
 Check condition
Driver’s door switch
 Driver’s door is opened while all the other doors are closed.
Passenger’s door switch
 Passenger’s door is opened while all the other doors are closed.
Rear door (RH) switch
 Rear door (RH) is opened while all the other doors are closed
Rear door (LH) switch
 Rear door (LH) door is opened while all the other doors are closed
Back door switch
 Back door is opened while all the other doors are closed
Driver’s door lock actuator switch (unlock switch)
 When the driver’s door is unlocked or locked
Interior lamp ON switch
 When turned from OFF to ON
Interior lamp OFF switch
 When turned from ON to OFF
OK: The M.U.T.-III sounds or the voltmeter needle fluctuates.

Q. Are the check result normal?
YES (All the signals are received normally) : Go to Step 2.
NO (All the door switch signals are not received normally) : Refer to ETACS - Input Signal Chart .
NO (The driver’s door lock actuator switch (unlock switch) : Refer to ETACS - Input Signal Chart .
NO (The interior lamp switch signal is not received normally) : Refer to ETACS - Input Signal Chart .

STEP 2. Retest the system.
Check that the right or left room lamp illuminates when the interior lamp switch is operated.

Q. Is the check result normal?
Go to Step 5.
Go to Step 3.

STEP 3. Connector check: D-419 ETACS-ECU connector, E-102 room lamp connector

Q. Is the check result normal?
Go to Step 4.
Repair the defective connector.

STEP 4. Check the wiring harness from D-419 ETACS-ECU connector terminal No.6 to E-102 room lamp connector terminal No.10.
note Prior to the wiring harness inspection, check intermediate connector D-130, joint connector D-34 and junction block connector D-410, and repair if necessary.

  • Check the power supply line for open circuit.

Q. Is the check result normal?
Replace the room lamp.
Repair the wiring harness.

STEP 5. Check the room lamp switch.
Check which position (ON or DOOR) of the room lamp switch does not activate the room lamp.

Q. Which switch position does not activate the lamp?
YES (The lamp illuminate normally) : The procedure is complete.
NO (The lamp does not illuminates at neither the ON nor DOOR position) : Go to Step 6.
NO (The lamp does not illuminate at the ON position) : Go to Step 6.
NO (The lamp does not illuminate at the DOOR position) : Go to Step 8.

STEP 6. Connector check: E-102 room lamp connector

Q. Is the check result normal?
Go to Step 7.
Repair the defective connector.

STEP 7. Check the bulbs of the room lamp.
Check that the room lamp bulbs are not burned out.

Q. Is the check result normal?
Replace the room lamp.
Replace the room lamp bulb.

STEP 8. Connector check: E-102 room lamp connector

Q. Is the check result normal?
Go to Step 9.
Repair the defective connector.

STEP 9. Check the bulbs of the room lamp.
Check that the room lamp bulbs are not burned out.

Q. Is the check result normal?
Go to Step 10.
Replace the room lamp bulb.

STEP 10. Check the wiring harness from D-419 ETACS-ECU connector terminal No.5 to E-102 room lamp connector terminal No.8.
note Prior to the wiring harness inspection, check intermediate connector D-130, joint connector D-34 and junction block connector D-410, and repair if necessary.

  • Check the earth wires for open circuit.

Q. Is the check result normal?
Replace the room lamp.
Repair the wiring harness.