Code No.B1138
Vehicle speed data fail
caution |
- If diagnosis
code No. B1138 is set, diagnose the CAN bus lines.
- If diagnosis code No. B1138 is set, check whether diagnosis code No. B1156 is also
set.
- When replacing the ECU, always check that the communication circuit is normal.
|
DIAGNOSIS FUNCTION
When the engine-ECU receives invalid or no vehicle speed signal via CAN, the KOS&OSS-ECU will
set diagnosis code No. B1138.
JUDGEMENT CRITERIA
Check Conditions
- The power supply mode is at ON without cranking.
Judgement Criterion
- Any of the following conditions is met, and two seconds or more have elapsed.
- The system does not receive any vehicle speed signal
from the engine-ECU.
- The system receives invalid vehicle speed signal from the engine-ECU.
PROBABLE CAUSES
- Malfunction of the CAN bus line
- Malfunction of engine-ECU
- Malfunction of KOS&OSS-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 2.
Repair the CAN bus line (Refer to GROUP 54C - Troubleshooting
).
STEP 2. M.U.T.-III diagnosis code
Check whether the KOS&OSS-ECU sets diagnosis code No. B1156.
Q.
Is the diagnosis code set?
Refer to Diagnosis code chart
.
Go to Step 3.
STEP 3. M.U.T.-III other system diagnosis code
|
(1)Check that the vehicle power can be turned "ON" and engine is started.
|
|
(2)Check the diagnosis code of engine-ECU.
|
Q.
Is the diagnosis code set?
Troubleshoot the engine-ECU (Refer to GROUP 13A - Troubleshooting
).
Then go to Step 4.
Go to Step 4.
STEP 4. Check whether the diagnosis code is set again.
|
(1)Check that the vehicle power can be turned "ON".
|
|
(2)Check again if the diagnosis code is set in the KOS&OSS-ECU.
|
Q.
Is the diagnosis code set?
Replace the KOS&OSS-ECU and register the chassis number (Refer to
).
Intermittent malfunction is suspected (Refer to GROUP 00 - How to Use
Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction
).