Code No. U1109: ETACS-ECU CAN timeout


caution
  • If there is any problem in the CAN bus lines, an incorrect diagnosis code may be set. Prior to this diagnosis, diagnose the CAN bus lines (Refer to GROUP 54C - CAN Bus Diagnostics Table ).
  • If diagnosis codes U1109 is set in ABS-ECU, always diagnose the CAN bus line. If there is any fault in the CAN bus lines, an incorrect diagnosis code may be set. In this case, the set diagnosis code is not highly reliable.
  • Whenever ECU is replaced, ensure that the CAN bus lines are normal.

OPERATION


The ABS-ECU communicates with the ETACS-ECU via the CAN bus lines.

DIAGNOSIS CODE SET CONDITIONS


If the ABS-ECU cannot receive any signal from the ETACS-ECU for a predetermined period, this diagnosis code will be set.
PROBABLE CAUSES

DIAGNOSIS PROCEDURE

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

Q. Is the check result normal?
Go to Step 3.
Repair the CAN bus lines (Refer to GROUP 54C - CAN Bus Diagnostics Table ). On completion, go to Step 2.

STEP 2. Diagnosis code recheck after resetting CAN bus lines
(1)Turn the ignition switch to the "LOCK" (OFF) position.
(2)Turn the ignition switch to the "ON" position.
(3)Erase the diagnosis code.
(4)Turn the ignition switch to the "LOCK" (OFF) position.
(5)Turn the ignition switch to the "ON" position.
(6)Check if the diagnosis code is set.

Q. Is diagnosis code No. U1109 set?
Go to Step 3.
This diagnosis is complete.

STEP 3. Use M.U.T.-III to confirm a diagnosis code of other systems.
Check whether a diagnosis code is set in the ETACS-ECU (Refer to GROUP 54A - ETACS-ECU, Troubleshooting, Diagnosis Code Chart ).

Q. Is the diagnosis code set?
Follow the relevant diagnosis code procedure (Refer to GROUP 54A - ETACS-ECU, Troubleshooting, Diagnosis Code Chart ). Then go to Step 7 .
Go to Step 4.

STEP 4. Use M.U.T.-III to confirm a diagnosis code of other systems.
Check whether an ETACS-ECU "time-out" related diagnosis code is set in other ECUs.

Q. Is the diagnosis code set?
Replace the ETACS-ECU (Refer to GROUP 54A - ETACS-ECU ).Then go to Step 7.
Go to Step 5.

STEP 5. Check whether the diagnosis code is set again.
Check again if the diagnosis code is set.
(1)Turn the ignition switch to the "LOCK" (OFF) position.
(2)Turn the ignition switch to the "ON" position.
(3)Erase the diagnosis code.
(4)Turn the ignition switch to the "LOCK" (OFF) position.
(5)Turn the ignition switch to the "ON" position.
(6)Check if the diagnosis code is set.
(7)Turn the ignition switch to the "LOCK" (OFF) position.

Q. Is diagnosis code No. U1109 set?
Replace the ETACS-ECU (Refer to GROUP 54A - ETACS-ECU ).Then go to Step 7.
Go to Step 6.

STEP 6. Check whether the diagnosis code is set again.
Check again if the diagnosis code is set.
(1)Turn the ignition switch to the "LOCK" (OFF) position.
(2)Turn the ignition switch to the "ON" position.
(3)Erase the diagnosis code.
(4)Turn the ignition switch to the "LOCK" (OFF) position.
(5)Turn the ignition switch to the "ON" position.
(6)Check if the diagnosis code is set.
(7)Turn the ignition switch to the "LOCK" (OFF) position.

Q. Is diagnosis code No. U1109 set?
Replace the hydraulic unit assembly (integrated with ABS-ECU) (Refer to ). Then go to Step 7.
The procedure is complete.

STEP 7. Check whether the diagnosis code is set again.
Check again if the diagnosis code is set.
(1)Turn the ignition switch to the "LOCK" (OFF) position.
(2)Turn the ignition switch to the "ON" position.
(3)Erase the diagnosis code.
(4)Turn the ignition switch to the "LOCK" (OFF) position.
(5)Turn the ignition switch to the "ON" position.
(6)Check if the diagnosis code is set.
(7)Turn the ignition switch to the "LOCK" (OFF) position.

Q. Is diagnosis code No. U1109 set?
Return to Step 1.
The procedure is complete.