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
- 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 light
- Central door locking system
Q: Is the check result normal?
YES : Go to Step 2.
NO : Refer to MALFUNCTION OF ETACS-ECU POWER SUPPLY CIRCUIT .
- STEP 2. Using scan tool MB991958, read CAN bus 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.
- Connect scan tool MB991958. Refer to "HOW TO CONNECT SCAN TOOL (M.U.T.-III) ".
- Turn the ignition switch to the "ON" position.
- Check whether the CAN bus lines related DTC is set.
- Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the DTC set?
YES : Repair the CAN bus line (Refer to CAN BUS DIAGNOSTICS TABLE ).
NO : Go to Step 3.
- STEP 3. 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.
- Connect scan tool MB991958. Refer to "HOW TO CONNECT SCAN TOOL (M.U.T.-III) ".
- Turn the ignition switch to the "ON" position.
- Check whether the ETACS-ECU related DTC is set.
- Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the DTC set?
YES : Diagnose the ETACS-ECU. Refer to DIAGNOSTIC TROUBLE CODE CHART .
NO : Go to Step 4.
- STEP 4. Using scan tool MB991958, check data list.
Check the signals related to the sunroof 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.- Connect scan tool MB991958. Refer to "HOW TO CONNECT THE SCAN TOOL (M.U.T.-III) ".
- Turn the ignition switch to the "ON" position.
- Check the data list of the ETACS.
- Turn the ignition switch to the "LOCK" (OFF) position.
OK: Normal conditions are displayed for all the items.
Q: Are the check result normal?
YES < Normal conditions are displayed for all the items. > : Go to Step 5.
NO < Normal condition is not displayed for item No. 254. > : Refer to INSPECTION PROCEDURE 2: THE IGNITION SWITCH (IG1) SIGNAL IS NOT RECEIVED .
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. .
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. .
- STEP 5. Retest the system.
Check that the sunroof timer function works normally.
Q: Is the check result normal?
YES : No action is necessary and testing is complete.
NO : Replace the ETACS-ECU. Check that the sunroof timer function works normally.