Code No.U1073: Bus-off



caution If diagnosis code U1073 is set in the SRS-ECU, diagnose the CAN main bus line.
caution Whenever the ECU is replaced, ensure that the input and output signal circuits are normal.

TROUBLE JUDGMENT


Diagnosis code No.U1073 will be stored when the SRS-ECU ceases CAN communication (bus off) and then resumes the communication by turning the ignition switch to the "LOCK" (OFF) position

COMMENTS ON TROUBLE SYMPTOM


The wiring harness wire or connectors may have loose, corroded, or damage terminals, or terminals pushed back in the connector, or the SRS-ECU may be defective.

PROBABLE CAUSES




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 54D, Diagnosis ).

STEP 2. Check whether the diagnosis code is reset.


Check again if the diagnosis code is set.
(1)Erase the diagnosis code.
(2)Ignition: "LOCK" (OFF) position to "ON"
(3)On completion, check that the diagnosis code is not reset.

Q. Is the check result satisfactory?

here is an intermittent malfunction such as poor engaged connector(s) or open circuit (Refer to GROUP 00, How to Cope with Intermittent Malfunction.)
Replace the SRS-ECU. On completion, check that the diagnosis code is not reset.