Active Stability Control System (ASC)
DTC U1417: Variant coding value invalid (includes faulty installation)
CAUTION:
- If there is any problem in the CAN bus lines, an incorrect diagnostic trouble code may be set. Prior to this diagnosis, diagnose the CAN bus lines CAN Bus Line Diagnostics Flow ).
- If diagnostic trouble code No.U1417 is set in ASC-ECU, always diagnose the CAN bus lines. If there is any fault in the CAN bus lines, an incorrect diagnostic trouble code may be set. In this case, the set diagnostic trouble code is not highly reliable.
- Before replacing the ECU, ensure that the communication circuit is normal.
- When diagnostic trouble code No.U1417 is set in ASC-ECU, the diagnostic trouble code may also be set in ETACS-ECU. When the diagnostic trouble code is set in ETACS-ECU, carry out the diagnosis of the diagnostic trouble code for ETACS-ECU first.
- When the hydraulic unit (integrated with ASC-ECU) is replaced, always carry out the calibration of the steering wheel sensor, the G and yaw rate sensor and brake fluid pressure sensor (Refer to Testing and Inspection , Testing and Inspection and Testing and Inspection ).
CIRCUIT OPERATION
ASC-ECU receives the vehicle information stored in the ETACS-ECU via CAN bus lines.
DTC SET CONDITIONS
ASC-ECU communicates with ETACS-ECU via CAN bus lines. This diagnostic trouble code is set when the vehicle information received from the ETACS-ECU is invalid.
PROBABLE CAUSES
- ETACS-ECU malfunction
- Engine control module malfunction
- ETACS-ECUs have been interchanged between two vehicles.
- ASC-ECU malfunction
- External noise interference
- ASC-ECUs have been interchanged between two vehicles.
DIAGNOSIS
STEP 1. Using scan tool MB991958, diagnose the CAN bus line.
Use scan tool to diagnose the CAN bus lines.
Q. Is the check result normal?
YES Go to Step 3.
NO Repair the CAN bus lines CAN Bus Diagnostics Chart).
On completion, go to Step 2.
STEP 2. DTC recheck after resetting CAN bus lines
Q. Is DTC U1417 set?
YES Go to Step 3.
NO The procedure is complete.
STEP 3. Using scan tool MB991958, other system DTC
Use scan tool to check whether any diagnostic trouble code related to vehicles information is set or not by the ETACS-ECU or engine control module.
Q. Is any DTC set?
YES Troubleshoot for the relevant diagnostic trouble code.
NO Go to Step 4.
STEP 4. ETACS-ECU coding data check
Programming and Relearning.
Q. Is the check result normal?
YES Go to Step 5.
NO Replace the ETACS-ECU Electronic Time and Alarm Control System (ETACS)-ECU Removal and Installation), and then go to Step 7.
STEP 5. Engine control module coding data check
Programming and Relearning.
Q. Is the check result normal?
YES Go to Step 6.
NO Replace the engine control module Removal and Replacement), and then go to Step 7.
STEP 6. Check part number of ETACS-ECU
Check the part number of ETACS-ECU.
Q. Is the check result normal?
YES Go to Step 7.
NO Replace the ETACS-ECU Electronic Time and Alarm Control System (ETACS)-ECU Removal and Installation), and then go to Step 7.
STEP 7. Check part number of ASC-ECU
Check the part number of ASC-ECU.
Q. Is the check result normal?
YES Go to Step 8.
NO Replace the hydraulic unit (integrated with ASC-ECU) (Refer to Service and Repair), and then go to Step 9.
STEP 8. Check whether the diagnostic trouble code is reset.
Erase the DTC.
Q. Is DTC U1417 set?
YES Replace the hydraulic unit (integrated with ASC-ECU) (Refer to Service and Repair), and then go to Step 9.
NO The trouble can be an intermittent malfunction How to Cope With Intermittent Malfunctions).
STEP 9. Check whether the diagnostic trouble code is reset.
Erase the DTC.
Q. Is DTC U1417 set?
YES Return to Step 1.
NO The procedure is complete.