Code No. C1804:
ACC Deactivation Disagreement <Vehicles with ACC/FCM>
caution |
Before replacing the ECU,
ensure that the communication circuit is normal.
|
OPERATION
The ASTC-ECU receives ACC control status signal from the ACC/FCM-ECU, and vehicle
control status signal from the engine-ECU via CAN bus lines, respectively.
DIAGNOSIS CODE SET CONDITIONS
If the information received from the ACC/FCM-ECU does not correspond to that
received from the engine-ECU, the ASTC-ECU will store the diagnosis code.
PROBABLE CAUSES
- Wiring harness or connector failure of CAN bus line
- Malfunction of engine-ECU
- Malfunction of ACC/FCM-ECU
- Malfunction of ASTC-ECU
|
STEP 1. M.U.T.-III Diagnosis code.
|
|
Use M.U.T.-III to check that the any diagnosis code other than C1804 is set in the ASTC-ECU.
|
|
Q.
Is the any diagnosis code other than C1804 set?
|
|
Troubleshoot for the relevant diagnosis code.
|
|
|
|
Go to Step 2.
|
|
|
|
STEP 2. M.U.T.-III Diagnosis code of other system.
|
|
Use M.U.T.-III to check that the diagnosis code No. C1777 is set in the ACC/FCM-ECU.
|
|
Q.
Is the diagnosis code No. C1777 set?
|
|
Troubleshoot for the relevant diagnosis code {Refer to GROUP 17 - Adaptive
Cruise Control System (ACC), Troubleshooting, Diagnosis Code Procedures: Code No. C1777 }.
|
|
|
|
Go to Step 3.
|
|
|
|
STEP 3. Check whether the diagnosis code is set again.
|
|
(1)Use the M.U.T.-III, erase the diagnosis code.
|
|
(2)Turn the ignition switch to the "LOCK" (OFF) position.
|
|
(3)Turn the ignition switch to the "ON" position.
|
|
(4)Press the ACC ON/OFF switch to turn the ACC to ON.
|
|
Q.
Is diagnosis code No. C1804 set?
|
|
Replace the ACC/FCM-ECU {Refer to GROUP 17 - Adaptive Cruise
Control System (ACC), ACC/FCM-ECU }. Then go to Step
4.
|
|
|
|
This diagnosis is complete.
|
|
|
|
STEP 4. Check whether the diagnosis code is set again.
|
|
(1)Use the M.U.T.-III, erase the diagnosis code.
|
|
(2)Turn the ignition switch to the "LOCK" (OFF) position.
|
|
(3)Turn the ignition switch to the "ON" position.
|
|
(4)Press the ACC ON/OFF switch to turn the ACC to ON.
|
|
Q.
Is diagnosis code No. C1804 set?
|
|
Replace the hydraulic unit (integrated with ASTC-ECU).
|
|
|
|
This diagnosis is complete.
|
|
|