If the diagnosis
code No. U0151 is set, be sure to diagnose the CAN bus line.
When replacing the ECU, always check that the communication circuit is normal.
DIAGNOSIS FUNCTION
WCM sets the diagnosis code No. U0151 when it cannot receive signals from SRS-ECU.
PROBABLE CAUSES
Malfunction of CAN bus line
Malfunction of SRS-ECU
Malfunction of WCM
Malfunction of ETACS-ECU
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 line (Refer to GROUP 54C -
Troubleshooting ).
On completion, go to Step 2.
STEP 2. M.U.T.-III other system diagnosis code
Check if the SRS-ECU-related diagnosis code is set.
Q.
Is the diagnosis code set?
Perform troubleshooting for SRS-ECU (Refer to GROUP 52B -
Troubleshooting ).
Go to Step 3.
STEP 3. M.U.T.-III other system diagnosis code
Check if the ETACS-ECU-related diagnosis code is set.
Q.
Is the diagnosis code set?
Perform troubleshooting for ETACS-ECU (Refer to GROUP 54A -
ETACS -
Troubleshooting).
Go to Step 4.
STEP 4. Check whether the diagnosis code is reset.
Recheck if the diagnosis code is set.
(1)Erase the diagnosis code.
(2)Turn the ignition switch from the LOCK (OFF) position to the ON position.
(3)Check if the diagnosis code is set.
Q.
Is the diagnosis code set?
Replace WCM and register the ID codes (Refer to ).
Intermittent malfunction is suspected (Refer to GROUP 00 -
How to Use
Troubleshooting/Inspection Service Points -
How to Deal with Intermittent
Malfunction ).