Code No. U0417 EPB (CAN message)


caution Before replacing the ECU, ensure that the communication circuit is normal.

OPERATION
The ASC-ECU communicates with the electric parking brake ECU via CAN bus lines.

DIAGNOSIS CODE SET CONDITIONS
The ASC-ECU will set the diagnosis code when any of the following conditions is satisfied:

  • The system receives an implausible signal from the electric parking brake ECU.
  • The electric parking brake actuator fails.
  • The emergency brake does not work as the ASC system fails.

PROBABLE CAUSES

  • Wiring harness or connector failure of CAN bus line
  • Electric parking brake system fails
  • ASC system fails

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III CAN bus diagnostics
Use M.U.T.-III to diagnose the CAN bus lines.

Q. Is the check result normal?
Go to Step 2
Repair the CAN bus lines (Refer to GROUP 54C - CAN Bus Diagnostics Table ).

STEP 2. M.U.T.-III Diagnosis code
Use M.U.T.-III to check that any diagnosis code other than code No. U0417 is set in ASC-ECU.

Q. Is the diagnosis code set?
Troubleshoot for the relevant diagnosis code (Refer to ).
Go to Step 3

STEP 3. M.U.T.-III Diagnosis code of other system
Use M.U.T.-III to check that any diagnosis code other than code No. U0415 is set in electric parking brake ECU.

Q. Is the diagnosis code set?
Troubleshoot for the relevant diagnosis code (Refer to GROUP 36 - Diagnosis Code Chart ).
Go to Step 4

STEP 4. Check whether the diagnosis code is set again.
(1)Erase the diagnosis code.
(2)Ignition switch "LOCK" (OFF)
(3)Ignition switch "ON"

Q. Is diagnosis code No.U0417 set?
Go to Step 5
The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to Cope with Intermittent Malfunction).

STEP 5. M.U.T.-III data list.
Check the data list (Refer to ).
Item No.
 Item name
 Normal condition
164
 A.S.C. dynamic brake fail
 Normal
OK: Normal condition is displayed.

Q. Is the check result normal?
Go to Step 6
Replace the electric parking brake ECU (Refer to GROUP 36 - Electric Parking Brake ECU ).

STEP 6. M.U.T.-III data list.
Check the data list (Refer to ).
Item No.
 Item name
 Normal condition
161
 EPB fail state
 Normal
OK: Normal condition is displayed.

Q. Is the check result normal?
The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to Cope with Intermittent Malfunction).
Replace the hydraulic unit assembly (integrated with ASC-ECU).