Diagnostic Procedure

Required Special Tools: 

• MB992006: Extra fine probe
• MB991223: Harness set
• MB991958: Scan Tool (M.U.T.-III Sub Assembly)
  • MB991824: Vehicles Communication Interface (V.C.I.)
  • MB991827: M.U.T.-III USB Cable
  • MB991910: M.U.T.-III Main Harness A

1. STEP 1. Check the power supply system. 

   With the ignition switch in the LOCK (OFF) position, check if the following function operates normally:

   • Hazard warning lamp

   Q: Is the check result normal? 

   1. YES:  Go to Step 2.
   2. NO:  Refer to MALFUNCTION OF ETACS-ECU POWER SUPPLY CIRCUIT .
2. STEP 2. Using scan tool MB991958, check data list. 

   Check the signals related to the power window timer function operation.

   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 THE SCAN TOOL (M.U.T.-III) ."
   2. Turn the ignition switch to the "ON" position.
   3. Check the data list of the ETACS.
      • Turn the ignition switch to the LOCK (OFF) position.
      • Close the driver's door.
      • Close the front passenger's door.

        Item No.	Item name	Normal condition
        254	IG voltage	Battery positive voltage
        256	Dr door ajar switch	Close
        257	As door ajar switch	Close

   4. Turn the ignition switch to the "LOCK" (OFF) position.

      OK: Normal condition is displayed. 

      Fig 1: Checking Signals Related To Central Door Locking System Operation

      

   Q: Is the check result normal? 

   1. YES < Normal conditions are displayed for all the items. >:  Go to Step 3.
   2. NO < Normal condition is not displayed for item No. 254. >:  Refer to INSPECTION PROCEDURE 2: "THE IGNITION SWITCH (IG1) SIGNAL IS NOT RECEIVED ."
   3. NO < Normal condition is not displayed for item No. 256. >:  Refer to INSPECTION PROCEDURE 5: "THE FRONT DOOR SWITCH (DRIVER'S SIDE) SIGNAL IS NOT RECEIVED ."
   4. NO < Normal condition is not displayed for item No. 257. >:  Refer to INSPECTION PROCEDURE 6: THE FRONT DOOR SWITCH (PASSENGER'S SIDE) SIGNAL IS NOT RECEIVED. .
3. STEP 3. Retest the system. 

   Check that the power window timer function works normally.

   Q: Is the check result normal? 

   1. YES:  No action is necessary and testing is complete.
   2. NO:  Replace the power window main switch. Check that the power window timer function works normally.