Lexus NX: Sleep Operation Failure of Occupant Classification ECU (B1796)
DESCRIPTION
During sleep mode, the occupant detection ECU monitors the condition of each sensor while the power switch is off. In this mode, if the occupant detection ECU detects an internal malfunction, DTC B1796 is stored.
| DTC No. | Detection Item | DTC Detection Condition | Trouble Area |
|---|---|---|---|
| B1796 | Sleep Operation Failure of Occupant Classification ECU | Occupant detection ECU malfunction. | Occupant detection ECU |
HINT:
Use the Techstream to check for DTCs of the occupant detection ECU, otherwise the DTCs cannot be read.
CAUTION / NOTICE / HINT
NOTICE:
When disconnecting the cable, some systems need to be initialized after the cable is reconnected.
Click here .gif)
PROCEDURE
| 1. | CHECK DTC |
(a) Turn the power switch on (IG), and wait for at least 60 seconds.
(b) Clear the DTCs.
Click here
HINT:
Use the Techstream to clear the DTCs of the occupant detection ECU, otherwise the DTCs cannot be cleared.
(c) Turn the power switch off.
(d) Turn the power switch on (IG), and wait for at least 60 seconds.
(e) Check for DTCs.
Click here
HINT:
DTCs other than DTC B1796 may be output at this time, but they are not related to this check.
| DTC B1796 is not output | .gif) | USE SIMULATION METHOD TO CHECK |
|
.gif)
| 2. | REPLACE OCCUPANT DETECTION ECU |
(a) Turn the power switch off.
(b) Disconnect the cable from the negative (-) auxiliary battery terminal, and wait for at least 90 seconds.
(c) Replace the occupant detection ECU.
Click here
HINT:
Perform the inspection using parts from a normal vehicle when possible.
|
| 3. | PERFORM ZERO POINT CALIBRATION |
(a) Connect the cable to the negative (-) auxiliary battery terminal, and wait for at least 2 seconds.
(b) Turn the power switch on (IG).
(c) Perform the zero point calibration.
Click here
|
| 4. | PERFORM SENSITIVITY CHECK |
(a) Perform the sensitivity check.
Click here
Standard:
27 to 33 kg (59.5 to 72.8 lb)
| NEXT | | END (OCCUPANT DETECTION ECU WAS DEFECTIVE) |
READ NEXT:
Trouble in Passenger Airbag ON/OFF Indicator
DESCRIPTION The occupant classification system detects the front passenger seat condition. It then displays the front passenger airbag condition (activated/not activated) using the passenger airbag ON
Components
COMPONENTS ILLUSTRATION *1 DECK FLOOR BOX LH *2 NO. 3 DECK BOARD SUB-ASSEMBLY *3 REAR DECK FLOOR BOX *4 AUXILIARY BATTERY NEGATIVE TERMINAL N*m (kgf*cm, ft.*lbf): Specified
SEE MORE:
Removal
REMOVAL CAUTION / NOTICE / HINT NOTICE: While the auxiliary battery is connected, even if the power switch is off, the brake control system activates when the brake pedal is depressed or any door courtesy switch turns on. Therefore, when servicing the brake system components, do not operate the brak
Parts Location
PARTS LOCATION ILLUSTRATION *A w/ Rear Seat Heater - - *1 AIR CONDITIONING CONTROL ASSEMBLY *2 SEAT HEATER SWITCH (for Driver Side) *3 SEAT HEATER SWITCH (for Front Passenger Side) *4 NO. 3 RELAY BLOCK
- RR S-HTR RELAY (w/ Rear Seat Heater)
*5 REFRESHING SEA
