Toyota CH-R Service Manual: Yaw Rate Sensor Module Malfunction (B1798,B1799)

Toyota CH-R Service Manual / Supplemental Restraint Systems / Occupant Classification System / Yaw Rate Sensor Module Malfunction (B1798,B1799)

DESCRIPTION

The occupant detection ECU receives signals from the acceleration sensor (airbag sensor assembly) and skid control ECU via CAN communication.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

B1798

Yaw Rate Sensor Module Malfunction

Acceleration signals are abnormal
  • Acceleration sensor (Airbag sensor assembly)
  • CAN communication system
  • Occupant detection ECU

B1799

Vehicle Stability Control ECU Malfunction

Vehicle speed signal from skid control ECU is abnormal
  • Skid control ECU (Brake actuator assembly)
  • CAN communication system
  • Occupant detection ECU

CAUTION / NOTICE / HINT

NOTICE:

After turning the ignition switch off, waiting time may be required before disconnecting the cable from the negative (-) battery terminal. Therefore, make sure to read the disconnecting the cable from the negative (-) battery terminal notices before proceeding with work.

Click here

HINT:

  • When DTC B1650/32 is stored as a result of troubleshooting for the airbag system, check the DTCs stored in the occupant detection ECU. When DTC B1798 or B1799 is output, perform troubleshooting for this DTC first.
  • If it is difficult to perform troubleshooting (wire harness inspection), remove the front passenger seat installation bolts to see under the seat cushion.
  • In the above case, lift and hold the seat so that it does not fall down. Hold the seat only as necessary because holding the seat for a long period of time may cause seat rail deformation.

PROCEDURE

1.

CHECK DTC (VEHICLE STABILITY CONTROL SYSTEM)

(a) Check for vehicle stability control system DTCs.

Click here

OK:

DTCs are not output.

NG

GO TO VEHICLE STABILITY CONTROL SYSTEM

OK

2.

CHECK CAN COMMUNICATION SYSTEM

(a) Using the Techstream, check if the CAN communication system is functioning normally.

OK:

CAN communication system is functioning normally.

HINT:

Refer to CAN Bus Check in CAN Communication System.

Click here

NG

GO TO CAN COMMUNICATION SYSTEM

OK

3.

CHECK DTC (HEALTH CHECK)

(a) Turn the ignition switch off.

(b) Connect the Techstream to the DLC3.

(c) Turn the ignition switch to ON and turn the Techstream on.

(d) Enter the following menus: System Select / Health Check.

OK:

DTCs are not output.

OK

USE SIMULATION METHOD TO CHECK

NG

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