Lexus NX: Precaution
PRECAUTION
CAUTION:
- This vehicle is equipped with a Supplemental Restraint System (SRS), which consists of a horn button assembly, instrument panel passenger airbag assembly, curtain shield airbag assembly, front seat airbag assembly, lower No. 1 instrument panel airbag assembly, front seat outer belt assembly, front seat cushion airbag assembly RH, front seat inner belt assembly, airbag ECU assembly, front airbag sensor, door side airbag sensor, side airbag sensor assembly, seat position airbag sensor, and occupant detection ECU. Failure to carry out service procedures in the correct sequence could cause SRS parts to unexpectedly deploy and possibly lead to serious injuries. Furthermore, if a mistake is made when servicing SRS parts, they may fail to operate when required. Before performing servicing (including installation/removal, inspection and replacement of parts), be sure to read the following precautions.
- Before starting work, wait at least 90 seconds after the power switch is turned off and after the cable is disconnected from the negative (-) auxiliary battery terminal (SRS parts are equipped with a backup power source. If work is started within 90 seconds of turning the power switch off and disconnecting the cable from the negative (-) auxiliary battery terminal, SRS parts may deploy).
- Do not expose SRS parts directly to hot air or flames.
-
Be sure to perform initialization of the occupant detection ECU under any of the following conditions. If initialization is not performed, the SRS may not operate properly.
- The occupant detection ECU is replaced.
- Accessories (seatback tray, seat cover, etc.) are installed to the vehicle.
- The passenger seat is removed from the vehicle, and then reinstalled or replaced.
- The passenger airbag ON/OFF indicator light (OFF) comes on when the passenger seat is not occupied.
- The vehicle is brought to a workshop for repair due to an accident or collision.
NOTICE:
- Malfunction symptoms of SRS parts are difficult to confirm. DTCs are the most important source of information when troubleshooting. During troubleshooting, always confirm DTCs before disconnecting the cable from the negative (-) auxiliary battery terminal.
- For minor collisions where SRS parts do not deploy, always inspect the SRS parts.
- Before performing repairs, remove the airbag sensors if any kind of impact is likely to occur to an airbag sensor during repairs.
- Never use SRS parts from another vehicle. When replacing SRS parts, replace them with new ones.
- Never disassemble or attempt to repair SRS parts.
- If an SRS part has been dropped, or if there are any cracks, dents or other defects in the case, bracket or connector, replace the SRS part with a new one.
- Use an ohmmeter/voltmeter with high impedance (10 kΩ/V minimum) for troubleshooting the electrical circuits.
- Information labels are attached to the periphery of SRS parts. Follow the cautions and instructions on the labels.
-
After work on the SRS is completed, perform the SRS warning light check.
Click here
.gif)
- If the vehicle is equipped with a mobile communication system, refer to the Precaution in the Introduction section.
-
After the power switch is turned off, there may be a waiting time before disconnecting the negative (-) auxiliary battery terminal.
Click here
-
When disconnecting and reconnecting the auxiliary battery
Click here
HINT:
When disconnecting and reconnecting the auxiliary battery, there is an automatic learning function that completes learning when the respective system is used.
Click here
-
After replacing the airbag ECU assembly, refer to initialization.
Click here
HINT:
In the airbag system, the airbag ECU assembly, front airbag sensor LH and RH, door side airbag sensor LH and RH, side airbag sensor assembly LH and RH, and seat position airbag sensor are collectively referred to as the airbag sensors.
HANDLING PRECAUTIONS FOR AIRBAG SENSORS
(a) Before starting the following operations, wait for at least 90 seconds after disconnecting the cable from the negative (-) auxiliary battery terminal.
(1) Replacement of the airbag sensors.
(2) Adjustment of the front/rear doors of the vehicle equipped with side airbags and curtain shield airbags (fitting adjustment).
(b) When connecting or disconnecting the airbag sensor connectors, make sure that each sensor is installed in the vehicle.
(c) Do not use airbag sensors which have been dropped during operation or transportation.
(d) Do not disassemble the airbag sensors.
INSPECTION PROCEDURE FOR VEHICLE INVOLVED IN ACCIDENT
(a) When the airbag has not deployed, confirm the DTCs by checking the SRS warning light. If there is any malfunction in the SRS airbag system, perform troubleshooting.
(b) When any of the airbags have deployed, replace the related airbag sensor and inspect its normal operation.
READ NEXT:
Parts Location
PARTS LOCATION ILLUSTRATION *1 FRONT SEAT OUTER BELT ASSEMBLY LH *2 FRONT SEAT OUTER BELT ASSEMBLY RH *3 FRONT SEAT AIRBAG ASSEMBLY LH *4 FRONT SEAT AIRBAG ASSEMBLY RH *5 CUR
System Diagram
SYSTEM DIAGRAM Transmitting ECU (Transmitter) Receiving ECU (Receiver) Signal Communication Method Airbag ECU Assembly Hybrid Vehicle Control ECU Crash detection signal CAN C
System Description
SYSTEM DESCRIPTION GENERAL (a) Deceleration sensors used for the airbag system are installed on various parts of the vehicle and calculate the deceleration rate of each part during a collision. (b) De
SEE MORE:
Terminals Of Ecu
TERMINALS OF ECU HINT: Perform the inspection from the harness side with the connectors connected. STEERING HEATER AND VIBRATION ECU (a) Measure the voltage or resistance according to the value(s) in the table below. Terminal No. (Symbol) Terminal Description Condition Specified Condition
Diagnosis System
DIAGNOSIS SYSTEM CHECK DLC3 (a) Check the DLC3. Click here INSPECT AUXILIARY BATTERY VOLTAGE (a) Measure the auxiliary battery voltage. Standard voltage: 11 to 14 V (power switch off) If the voltage is below 11 V, recharge or replace the auxiliary battery.
