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INSPECTION PROCEDURE 4: Vehicle speed-dependent unfolding function does not work normally.
 
 
cautionWhenever the ECU is replaced, ensure that the input and output signal circuits are normal.
 
 
 
 
 
CIRCUIT OPERATION
The ETACS-ECU calculates the intermittent wiper interval according to the vehicle speed signal which is sent by the ASC-ECU.
  • Ignition switch (IG1)
 
 
 
TECHNICAL DESCRIPTION (COMMENT)
If this function does not work normally, input signal circuit(s) or the ETACS-ECU may be defective. Also, with a configuration function, the door mirrors may be set to a mode in which the vehicle speed-dependent unfolding function is not activated.
 
 
 
TROUBLESHOOTING HINTS
  • Faulty vehicle speed signal
  • The CAN bus line is defective.
  • Malfunction of ETACS-ECU
  • Damaged wiring harness and connectors
 
 
 
 
DIAGNOSIS
Required Special Tools:
  • MB991223: Harness Set
  • MB992006: Extra Fine Probe
  • MB991958: Scan Tool (M.U.T.-III Sub Assembly)
    • MB991824: V.C.I.
    • MB991827: M.U.T.-III USB Cable
    • MB991910: M.U.T.-III Main Harness A
STEP 1. Check the ETACS configuration function.
Use the ETACS configuration function to confirm that "AUTO FOLD MIRROR" is set to "Open Vehicle SPD".
Is the check result normal?
Go to Step 2.
Use the ETACS configuration function to set "AUTO FOLD MIRROR" to "Open Vehicle SPD" (Refer to ).
 
STEP 2. Use the scan tool MB991958 to diagnose the CAN bus lines.
Check if an ETACS-related diagnosis trouble code is set.
Is the CAN bus normal?
Go to Step 3.
Repair the CAN bus line (Refer to GROUP 54C - CAN Bus Diagnostic Chart ).
 
STEP 3. Use the scan tool MB991958 to diagnose other system diagnostic trouble code
Connect the scan tool. Refer to GROUP 54A ETACS, "Diagnostic function" .
Check that the ASC-ECU sets a diagnostic trouble code.
Is the diagnostic trouble code set?
Diagnose the ASC-ECU (Refer to GROUP 35C - Diagnostic Trouble Code Chart ).
Go to Step 4.
 
STEP 4. Retest the system.
Check that the vehicle speed-dependent unfolding function of the door mirrors works normally.
Is the check result normal?
Intermittent malfunction (Refer to the basic Service Manual, GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction .)
Replace ETACS-ECU.