Lexus RX (RX 350L, RX450h) 2016-2025 Repair Manual: Yaw Rate Sensor Module Malfunction (B1798,B1799)
DESCRIPTION
The occupant detection ECU receives signals from the acceleration sensor (airbag sensor assembly*1 or yaw rate sensor assembly*2) 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 |
|
| B1799 | Vehicle Stability Control ECU Malfunction | Vehicle speed signal from skid control ECU is abnormal |
|
- *1: w/o VDIM
- *2: w/ VDIM
CAUTION / NOTICE / HINT
NOTICE:
After turning the engine 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 .gif)
HINT:
- When DTC B1650 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 | .gif) | GO TO VEHICLE STABILITY CONTROL SYSTEM |
|
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| 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 |
|
| 3. | CHECK DTC (HEALTH CHECK) |
(a) Turn the engine switch off.
(b) Connect the Techstream to the DLC3.
(c) Turn the engine switch on (IG) 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 | | GO TO OTHER DIAGNOSTIC TROUBLE CODE CHART |
Occupant Classification ECU Malfunction (B1795)
DESCRIPTION DTC B1795 is stored when a malfunction is detected in the occupant detection ECU. DTC No. Detection Item DTC Detection Condition Trouble Area B1795 Occupant Classification E ...
Lost Communication with Multi-axis Acceleration Sensor Module (U0125,U0129)
DESCRIPTION The occupant detection ECU sends/receives signals to/from each ECU via CAN communication. DTC No. Detection Item DTC Detection Condition Trouble Area U0125 Lost Communicatio ...
Other materials:
Lexus RX (RX 350L, RX450h) 2016-2025 Repair Manual > Immobiliser System: Diagnosis System
DIAGNOSIS SYSTEM DESCRIPTION (a) The certification ECU (smart key ECU assembly) and ECM control the vehicle immobiliser system functions. Immobiliser system data and Diagnostic Trouble Codes (DTCs) can be read through the vehicle Data Link Connector 3 (DLC3). In some cases, a malfunction may be occu ...
Lexus RX (RX 350L, RX450h) 2016-2025 Repair Manual > Immobiliser System: Short to GND in Immobiliser System Power Source Circuit (B278A)
DESCRIPTION When there is a short to GND in the power supply for the transponder key amplifier of the engine switch, the certification ECU (smart key ECU assembly) stores this DTC. DTC No. Detection Item DTC Detection Condition Trouble Area Note B278A Short to GND in Immobiliser Sys ...
Lexus RX (RX 350L, RX450h) 2016-{YEAR} Owners Manual
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Lexus RX (RX 350L, RX450h) 2016-{YEAR} Repair Manual
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