Before replacing the ECU,
ensure that the power supply circuit, the earth circuit and the communication circuit are normal.
JUDGEMENT CRITERIA
ETACS-ECU sends the diagnosis code (U code) detection permission or prohibition signal
to each ECU connected to the CAN bus line. If the radio and CD player cannot receive the diagnosis
code (U code) detection permission or prohibition signal for 5 seconds after turning the electric
motor switch to ON position, diagnosis code U1190 will be set.
PROBABLE CAUSES
Malfunction of the ETACS-ECU
Malfunction of CAN bus line
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 ).
On completion, go to Step 3.
STEP 2. Check whether the diagnosis code is reset.
Check again if the diagnosis code is set to the radio and CD player.
(1)Erase the diagnosis code.
(2)Turn the ignition switch from the "LOCK" (OFF) position to the "ON" position.
(3)On completion, check that the diagnosis code is reset.
Q.
Is the diagnosis code set?
Replace the ETACS-ECU. (Refer to GROUP 54A - ETACS .)
Then go to Step 3.
The procedure is complete.
STEP 3. Check whether the diagnosis code is reset.
Recheck if the diagnosis code is set to the radio and CD player.
(1)Erase the diagnosis code.
(2)Turn the ignition switch from the "LOCK" (OFF) position to the "ON" position.
(3)On completion, check that the diagnosis code is reset.