Code No. U1901:
K-line slave lost among BMUs
Code No. U1911: K-line between BMUs reception error
caution | If there is any problem in the CAN bus lines,
an incorrect diagnosis code may be set. Prior to this diagnosis, always diagnose the CAN bus lines. |
OPERATION
- The CAN communication between BMUs and EV-ECU is backed
up by the K-LINE communication.
DIAGNOSIS CODE SET CONDITIONS
- If the K-LINE (back-up) communication data from the BMU
cannot be received, the diagnosis code No. U1901 will be set.
- If the K-LINE (back-up) communication data from the BMU is parity error or checksum,
the diagnosis code No. U1911 will be set.
PROBABLE CAUSES
- Damaged wiring harness or connector(s)
- Malfunction of the BMU system
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?
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Go to Step 3. |
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Repair the CAN bus line. (Refer to GROUP 54C - Troubleshooting .)
Then go to Step 2. |
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STEP 2. Check whether the diagnosis code is reset. |
Check again if the diagnosis code No. U1901 or No. U1911 is set to the EV-ECU. |
(1)Erase the stored diagnosis code. |
(2)Set the electric motor switch from the "LOCK" (OFF) position to the "ON" position. |
(3)Check if the diagnosis code is set. |
Q.
Is the diagnosis code set?
|
Go to Step 3. |
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This diagnosis is complete. |
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STEP 3. Connector check: C-107 BMU connector, C-106 EV-ECU connector |
Q.
Is the check result normal?
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Go to Step 4. |
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Repair the damaged connector. |
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STEP 4. Check the wiring harness between C-107 BMU connector terminal No. 8 and C-106 EV-ECU connector terminal No. 16. |
Check the signal lines for open circuit. |
Q.
Is the check result normal?
|
Go to Step 5. |
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Repair the wiring harness. |
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STEP 5. Use M.U.T.-III to confirm a diagnosis code of other systems. |
Check if the diagnosis code is set to BMU. |
Q.
Is the diagnosis code set?
|
Carry out troubleshooting for the BMU. (Refer to Diagnosis Code Chart .)
Then go to Step 6. |
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Go to Step 6. |
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STEP 6. Diagnosis code recheck |
Check again if the diagnosis code is set to the EV-ECU. |
(1)Erase the stored diagnosis code. |
(2)Set the electric motor switch from the "LOCK" (OFF) position to the "ON" position. |
(3)Check if the diagnosis code is set. |
Q.
Is the diagnosis code set?
|
Return to Step 1. |
|
The diagnosis is complete. |
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