Code No.U0019 Bus off (CAN-B)


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.
  • Before replacing the radio and CD player, be sure to check that the power supply circuit, earth circuit, and communication circuit are normal.

TROUBLE JUDGMENT
When the radio and CD player is returned from the bus off state, or when the bus error is indicated to the radio and CD player state, the diagnosis code U0019 (CAN-B) is set.

COMMENTS ON TROUBLE SYMPTOM
The radio and CD player, power supply for the radio and CD player, earth circuit, or CAN bus line may have a problem.

PROBABLE CAUSES

  • Malfunctions of radio and CD player
  • Malfunction of CAN bus line wiring harness and connector

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. Check whether the M.U.T.-III can communicate with the radio and CD player.

Q. Is the check result normal?
Erase the diagnosis code. This diagnosis is complete.
Check the power supply circuit of the radio and CD player, and repair if necessary.