Code No. B1731: Communication error with the engine-ECU
| caution | If diagnosis code No.B1731
is set in the immobilizer-ECU, diagnose the CAN bus lines. |
| caution | Whenever the ECU is replaced, ensure that the input and output
signal circuits are normal. |
TROUBLE JUDGMENT
COMMENT ON TROUBLE SYMPTOM
PROBABLE CAUSES
- Malfunction of engine-ECU
- Malfunction of immobilizer-ECU
- Damaged harness wires and connectors
DIAGNOSIS PROCEDURE
STEP 1. M.U.T.-III CAN bus diagnostics.
Q.
Is the check result normal?
STEP 2. Check whether the diagnosis code is reset.
| (1)Erase the diagnosis code. |
| (2)Turn the ignition switch to the "LOCK" (OFF) position once, and then turn it to
the "ON" position again. |
| (3)Check that diagnosis code No.B1731 is not set as a current trouble. |
Q.
Is diagnosis code No.B1731 set?
STEP 3. Check whether the diagnosis code is reset.
| (1)Erase the diagnosis code. |
| (2)Turn the ignition switch to the "LOCK" (OFF) position once, and then turn it to
the "ON" position again. |
| (3)Check that diagnosis code No.B1731 is not set as a current trouble. |
Q.
Is diagnosis code No.B1731 set?