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 audio unit, be sure to check that the power supply circuit,
earth circuit, and communication circuit are normal.
TROUBLE JUDGMENT
If the audio unit continuously apply the voltage of 2 V or more to the speakers for 1
minute or more, it is determined that the offset voltage is exceeded, and then the diagnosis
code is set.
COMMENTS ON TROUBLE SYMPTOM
The audio unit or CAN bus line may have a problem.
PROBABLE CAUSES
Malfunctions of audio unit
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 diagnosis code is reset.
Check again if the diagnosis code is set to the audio unit.
(1)Erase the diagnosis code.
(2)Turn the ignition switch from "LOCK" (OFF) position to "ON" position.
(3)Check if diagnosis code is set.
Q.
Is the diagnosis code set?
Replace the audio unit.
The trouble can be an intermittent malfunction (Refer to GROUP 00 -
How
to use Troubleshooting/inspection Service Points -
How to Cope with Intermittent
Malfunction ).