If diagnosis
code U1073 is set in the multi display station, always diagnose the CAN bus lines.
Whenever the ECU is replaced, ensure that the communication circuit is normal.
TROUBLE JUDGMENT
If the multi display station ceases communicating once (i.e. bus off) and then returns
to it, the multi display station will not communicate for three minutes immediately after that
point. This three-minute period is called "Penalty mode." Immediately after the multi display
station returns to communication, the diagnosis code is set.
COMMENTS ON TROUBLE SYMPTOM
The CAN bus line wiring harness, connector(s), or the multi display station may be defective.
POSSIBLE CAUSES
Damaged harness wires and connectors
Malfunction of multi display station
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 satisfactory?
Go to Step 2.
Repair the CAN bus lines. (Refer to GROUP 54C, Diagnosis -
Can Bus Diagnostics
Table ). Repair the CAN bus line and go to Step 3.
STEP 2. Check whether the diagnosis code is reset.
Recheck if the diagnosis code is set.
(1)Erase the diagnosis code.
(2)Turn the ignition switch to "ON" position.
(3)Check if the diagnosis code is set.
Q.
Is the check result satisfactory?
If the trouble is solved, it is determined that there is an intermittent malfunction
such as poor engaged connector(s) or open circuit (Refer to GROUP 00, How to Use Troubleshooting/Inspection
Service Points -
How to Cope with Intermittent Malfunctions ).
Replace multi display station and then go to step 3.
STEP 3. Check whether the diagnosis code is reset.