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 ).
Whenever ECU is replaced, ensure that the CAN bus lines are normal.
OPERATION
ASC-ECU receives signal from the combination meter via the CAN bus lines.
DIAGNOSIS CODE SET CONDITIONS
When the signal from the combination meter shows rejection, ASC-ECU determines that the
malfunction has occurred and sets this diagnosis.
PROBABLE CAUSES
Malfunction of combination meter assembly
Malfunction of ASC-ECU
DIAGNOSIS PROCEDURE
STEP 1. M.U.T.-III CAN bus diagnostics
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
Q.
Is the diagnosis code No. U1128 set?
Go to Step 3.
This diagnosis is complete.
STEP 3. M.U.T.-III Diagnosis code of other systems
Check if a diagnosis code is set in the combination meter.
Q.
Is the diagnosis code set?
Diagnose the combination meter. Then go to Step 5.
Go to Step 4.
STEP 4. M.U.T.-III diagnosis code
Check if the diagnosis code other than code No. U1128 is set from ASC-ECU.
Q.
Is the diagnosis code other than code No. U1128 set?
Troubleshoot for the relevant diagnosis code (Refer to ).
Replace the combination meter (Refer to GROUP 54A - combination meter
assembly ). Then go to Step 5.
STEP 5. Diagnosis code recheck
(1)Erase the diagnosis code.
(2)Turn the electric motor switch from "LOCK" (OFF) position to "ON" position.
Q.
Is the diagnosis code No. U1128 set?
Replace the hydraulic unit (integrated with ASC-ECU) (Refer to ).
Then go to Step 6.
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/How
to Cope with Intermittent Malfunctions ).
STEP 6. Diagnosis code recheck
(1)Erase the diagnosis code.
(2)Turn the electric motor switch from "LOCK" (OFF) position to "ON" position.
Go to Step 3.
Repair the CAN bus lines (Refer to GROUP 54C - CAN Bus Diagnostics Table 
).
On completion, go to Step 2.