Code No.C1388: Yaw rate sensor active check error


caution
  • If there is any problem in the CAN bus lines, an incorrect diagnosis code may be set. Prior to this diagnosis, diagnose the CAN bus lines (Refer to GROUP 54C, CAN Bus Diagnosis Table ).
  • Whenever ECU is replaced, ensure that the CAN bus lines are normal.

OPERATION
The G and yaw rate sensor output signal is sent to TCL/ASC-ECU via the CAN bus lines.

DIAGNOSIS CODE SET CONDITIONS
TCL/ASC-ECU monitors the G and yaw rate sensor output signal, and if the signal from the G and yaw rate sensor has a trouble, the ECU determines that a malfunction has occurred and sets the diagnosis code.

PROBABLE CAUSES

  • Malfunction of the G and yaw rate sensor
  • Malfunction of TCL/ASC-ECU

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 3.
Repair the CAN bus lines. (Refer to GROUP 54C - Troubleshooting .) On completion, go to Step 2.

STEP 2. Diagnosis code recheck after resetting CAN bus lines

Q. Is the diagnosis code No.C1388 set?
Go to Step 3.
This diagnosis is complete.

STEP 3. M.U.T.-III data list
Check the following data list.(Refer to .)

  • Item No.12: Yaw rate sensor

Q. Is the check result normal?
Go to Step 4.
Replace the G and yaw rate sensor (Refer to ). Then go to Step 5.

STEP 4. Diagnosis code recheck
(1)Ignition switch: "ON"
(2)Erase the diagnosis code.
(3)Ignition switch: "LOCK" (OFF)
(4)Start the engine.
(5)Drive the vehicle at 40 km/h or more.

Q. Is the diagnosis code No.C1388 set?
Replace the hydraulic unit (integrated with TCL/ASC-ECU) (Refer to ). Then go to Step 5.
Intermittent malfunction (Refer to GROUP 00 - How to Cope with Intermittent Malfunction ).

STEP 5. Diagnosis code recheck
(1)Ignition switch: "ON"
(2)Erase the diagnosis code.
(3)Ignition switch: "LOCK" (OFF)
(4)Start the engine.
(5)Drive the vehicle at 40 km/h or more.

Q. Is the diagnosis code No.C1388 set?
Return to Step 1.
This diagnosis is complete.