Inspection Procedure 1: The Front Dome Light Does Not Illuminate Normally: Diagnosis

Required Special Tools: 

• MB992006: Extra fine probe
• MB991223: Harness set

1. STEP 1. Rear dome light operation check 

   Check that the rear dome light illuminates and extinguishes normally.

   Q: Is the check result normal? 

   • YES:  Go to Step  4.
   • NO:  Go to Step 2.
2. STEP 2. Using scan tool (M.U.T.-III), read the diagnostic trouble code 
   CAUTION: To prevent damage to scan tool (M.U.T.-III), always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool (M.U.T.-III).
   1. Connect scan tool (M.U.T.-III). Refer to "HOW TO CONNECT SCAN TOOL (M.U.T.-III) ".
   2. Turn the ignition switch to the "ON" position.
   3. Check whether the ETACS-ECU related DTC is stored.
   4. Turn the ignition switch to the "LOCK" (OFF) position.

   Q: Is the DTC stored? 

   • YES:  Troubleshoot the ETACS-ECU. Refer to DIAGNOSTIC TROUBLE CODE TABLE .
   • NO:  Go to Step 3.
3. STEP 3. Using scan tool (M.U.T.-III), check data list. 

   Use the ETACS-ECU service data to check the signals related to the operation of front dome light.

   • Turn the ignition switch to the LOCK (OFF) position.
   • Remove the ignition key from the ignition key cylinder.
   • Open each door.

     Item No.	Item name	Normal condition
     228	Dr door unlock	ON
     254	IG voltage	1 V or less
     256	Dr door ajar switch	Open
     257	As door ajar switch	Open
     258	RR door ajar switch	Open
     259	RL door ajar switch	Open
     264	Handle lock switch	Key in → Key out

     OK: Normal conditions are displayed for all the items. 

   Q: Is the check result normal? 

   Normal conditions are displayed for all the items.:  Replace the ETACS-ECU.

   Normal condition is not displayed for item No. 228.:  Troubleshoot the ETACS-ECU. Refer to INSPECTION PROCEDURE 4: THE FRONT DOOR LOCK ACTUATOR (DRIVER'S SIDE) SIGNAL IS NOT RECEIVED .

   Normal condition is not displayed for item No. 254.:  Troubleshoot the ETACS-ECU. Refer to INSPECTION PROCEDURE 2: THE IGNITION SWITCH (IG1) SIGNAL IS NOT RECEIVED .

   Normal condition is not displayed for item No. 256.:  Troubleshoot the ETACS-ECU. Refer to INSPECTION PROCEDURE 5: THE FRONT DOOR SWITCH (DRIVER'S SIDE) SIGNAL IS NOT RECEIVED .

   Normal condition is not displayed for item No. 257.:  Troubleshoot the ETACS-ECU. Refer to INSPECTION PROCEDURE 6: THE FRONT DOOR SWITCH (PASSENGER'S SIDE) SIGNAL IS NOT RECEIVED .

   Normal condition is not displayed for item No. 258.:  Troubleshoot the ETACS-ECU. Refer to INSPECTION PROCEDURE 7: THE REAR DOOR SWITCH (RH) SIGNAL IS NOT RECEIVED .

   Normal condition is not displayed for item No. 259.:  Troubleshoot the ETACS-ECU. Refer to INSPECTION PROCEDURE 8: THE REAR DOOR SWITCH (LH) SIGNAL IS NOT RECEIVED .

   Normal condition is not displayed for item No. 264.:  Troubleshoot the ETACS-ECU. Refer to INSPECTION PROCEDURE 3: THE KEY REMINDER SWITCH SIGNAL IS NOT RECEIVED. < VEHICLES WITHOUT KOS > .

4. STEP 4. Front dome light bulb check 

   Check that the front dome light bulb is normal.

   Q: Is the check result normal? 

   • YES:  Go to Step 5.
   • NO:  Replace the front dome light bulb.
5. STEP 5. Check of open circuit in (LP+1) line between the front dome light connector and ETACS-ECU connector. 

   Q: Is the check result normal? 

   • YES:  Go to Step 6.
   • NO:  Repair the connector(s) or wiring harness.
6. STEP 6. Check of open circuit in (RLP-) line between the front dome light connector and ETACS-ECU connector. 

   Q: Is the check result normal? 

   • YES:  Go to Step 7.
   • NO:  Repair the connector(s) or wiring harness.
7. STEP 7. Check of open circuit in ground line between the front dome light connector and ground. 

   Q: Is the check result normal? 

   • YES:  Replace the front dome light, and then go to Step 8.
   • NO:  Repair the connector(s) or wiring harness.
8. STEP 8. Retest the system 

   Check that the front dome light illuminates/extinguishes normally.

   Q: Is the check result normal? 

   • YES:  The trouble can be an intermittent malfunction (Refer to HOW TO COPE WITH INTERMITTENT MALFUNCTION ).
   • NO:  Replace the ETACS-ECU.