Inspection Procedure 2: The rear dome light does not illuminate normally: Diagnosis

Required Special Tools:

• MB991958: Scan Tool (M.U.T.-III Sub Assembly)
  • MB991824: Vehicle Communication Interface (V.C.I.)
  • MB991827: M.U.T.-III USB Cable
  • MB991910: M.U.T.-III Main Harness A (Vehicles with CAN communication system)

1. STEP 1. Front dome light operation check 

   Check that the front dome light illuminates and extinguishes normally.

   Q: Does rear dome light work normally? 

   YES:  Go to Step 2.

   NO:  Replace the ETACS-ECU.

2. STEP 2. Using scan tool MB991958, read the diagnostic trouble code. 
   CAUTION: To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991958.
   1. Connect scan tool MB991958. 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 set.
   4. Turn the ignition switch to the "LOCK" (OFF) position.

   Q: Is the DTC set? 

   YES:  Diagnose the ETACS-ECU. Refer to DIAGNOSIS  .

   NO:  Go to Step 3.

   Fig 1: Connecting Scan Tool To Data Link Connector

   Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
3. STEP 3. Using scan tool MB991958, check data list. 

   Use the ETACS-ECU data list to check the signals related to the rear dome light.

   • Turn the ignition switch to the "LOCK" (OFF) position.
   • Remove the ignition key from the ignition key cylinder.
   • Open each door.
   • Open the liftgate.
     ETACS-ECU DATA LIST
     
     

     Item No.	Item name	Normal conditions
     Item 228	Dr door unlock	ON
     Item 254	IG voltage	Battery voltage
     Item 256	Dr door ajar switch	Open
     Item 257	As door ajar switch	Open
     Item 258	RR door ajar switch	Open
     Item 259	RL door ajar switch	Open
     Item 260	Trunk/gate trunk ajar switch	Open
     Item 264	Handle lock switch	Key in → Key out

   Q: Does scan tool MB991958 display the items "Dr door unlock", "IG voltage", "Dr door ajar switch", "As door ajar switch", "RR door ajar switch", "RL door ajar switch", "Trunk/gate trunk ajar switch" and "Handle lock switch" as normal condition? 

   YES< Normal conditions are displayed for all items. >:  Go to Step 4.

   NO< Normal condition is not displayed for item No. 228. >:  Troubleshoot the ETACS-ECU. Refer to INSPECTION PROCEDURE 4 "ETACS-ECU DOES NOT RECEIVE ANY SIGNAL FROM THE FRONT DOOR LOCK ACTUATOR"  .

   NO< Normal condition is not displayed for item No. 254. >:  Troubleshoot the ETACS-ECU. Refer to INSPECTION PROCEDURE 4 "ETACS-ECU DOES NOT RECEIVE ANY SIGNAL FROM THE IGNITION SWITCH (IG1)"  .

   NO< Normal condition is not displayed for item No. 256. >:  Troubleshoot the ETACS-ECU. Refer to INSPECTION PROCEDURE 5 "ETACS-ECU DOES NOT RECEIVE ANY SIGNAL FROM THE FRONT DOOR SWITCH (LH)"  .

   NO< Normal condition is not displayed for item No. 257. >:  Troubleshoot the ETACS-ECU. Refer to INSPECTION PROCEDURE 6 "ETACS-ECU DOES NOT RECEIVE ANY SIGNAL FROM THE FRONT DOOR SWITCH (RH)"  .

   NO< Normal condition is not displayed for item No. 258. >:  Troubleshoot the ETACS-ECU. Refer to INSPECTION PROCEDURE 7 "ETACS-ECU DOES NOT RECEIVE ANY SIGNAL FROM THE REAR DOOR SWITCH (LH)"  .

   NO< Normal condition is not displayed for item No. 259. >:  Troubleshoot the ETACS-ECU. Refer to INSPECTION PROCEDURE 8 "ETACS-ECU DOES NOT RECEIVE ANY SIGNAL FROM THE REAR DOOR SWITCH (RH)"  .

   NO< Normal condition is not displayed for item No. 260. >:  Troubleshoot the ETACS-ECU. Refer to INSPECTION PROCEDURE 9 "ETACS-ECU DOES NOT RECEIVE ANY SIGNAL FROM THE LIFTGATE SWITCH"  .

   NO< Normal condition is not displayed for item No. 264. >:  Troubleshoot the ETACS-ECU. Refer to INSPECTION PROCEDURE 3 "ETACS-ECU DOES NOT RECEIVE ANY SIGNAL FROM THE KEY REMINDER SWITCH"  .

4. STEP 4. Check rear dome light connector D-10 for loose, corroded or damaged terminals, or terminals pushed back in the connector. 

   Q: Is rear dome light connector D-10 in good condition? 

   YES:  Go to Step 5.

   NO:  Repair the damaged parts.

5. STEP 5. Rear dome light bulb check 

   Check that the rear dome light bulb is normal.

   Q: Does rear dome light work normal? 

   YES:  Go to Step 6.

   NO:  Replace the rear dome light bulb.

6. STEP 6. Check ETACS-ECU connector C-316 for loose, corroded or damaged terminals, or terminals pushed back in the connector. 

   Q: Is ETACS-ECU connectors C-311 in good condition? 

   YES:  Go to Step 7.

   NO:  Repair the damaged parts.

7. STEP 7. Check the wiring harness between rear dome light D-10 connector terminal (No. 1/2) and ETACS-ECU connector C-316 (terminal No. 6/5) 

   Q: Is wiring harness between rear dome light connector D-10 (terminal No. 1/2) and ETACS-ECU connector C-316 (terminal No. 6/5) in good condition? 

   YES:  Go to Step 8.

   NO:  Repair the wiring harness.

8. STEP 8. Retest the system 

   Check that the rear dome light illuminates/extinguishes normally.

   Q: Does rear dome light work normal? 

   YES:  The trouble can be an intermittent malfunction (Refer to HOW TO COPE WITH INTERMITTENT MALFUNCTION ).

   NO:  Replace the ETACS-ECU.