If the EPS-ECU
sets the diagnosis code No. U1128, diagnose the CAN bus lines. If there is any fault in the
CAN bus lines, an incorrect diagnosis code may be set.
Before replacing ECU, ensure that the communication circuit is normal.
TROUBLE JUDGEMENT
EPS-ECU receives the odometer data from the combination meter via CAN bus lines. If the
EPS-ECU receives the odometer containing failure information for 41 times, the diagnosis code
No. U1128 will be set.
COMMENT ON TROUBLE SYMPTOM
Current trouble
The odometer of combination meter, combination meter itself, or EPS-ECU itself may
be faulty.
Past trouble
Carry out diagnosis with particular emphasis on wiring harness and connectors relevant
to the combination meter (odometer-related). For diagnosis procedures, refer to "How to Cope
with Historic Trouble" (GROUP 00 - How to Use Troubleshooting/Inspection Service Points ).
PROBABLE CAUSES
Defective harness wire(s) or connector(s)
Malfunction of the combination meter
Malfunction of the EPS-ECU
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 satisfactory?
Go to Step 2.
Repair the CAN bus lines. (Refer to GROUP 54C, Troubleshooting .)
STEP 2. Use M.U.T.-III to confirm a diagnosis code of other systems.
Check if a combination meter-related diagnosis code is set.
Q.
Is the diagnosis code set?
Diagnose the combination meter. (Refer to GROUP 54A - Troubleshooting .)
Go to Step 3.
STEP 3. Diagnosis code recheck
Recheck if the diagnosis code is set.
(1)Turn the electric motor switch to the "LOCK" (OFF) → "ON" position.
(2)Check if the diagnosis code No. U1128 is set as a current trouble.
Q.
Is diagnosis code C1128 set?
Replace the EPS-ECU, and then go to Step 4 .
An intermittent malfunction such as poor contact or open circuit is suspected
in the combination meter (odometer-related). Refer to GROUP 00,How to Use Troubleshooting/Inspection
Service Point - How to Cope with Intermittent Malfunction .)
STEP 4. Diagnosis code recheck
Recheck if the diagnosis code is set.
(1)Turn the electric motor switch to the "LOCK" (OFF) → "ON" position.
(2)Check if the diagnosis code No. U1128 is set as a current trouble.
).
Go to Step 2.
Repair the CAN bus lines. (Refer to GROUP 54C, Troubleshooting 