Lexus NX: Occupant Classification ECU Malfunction (B1795)

DESCRIPTION

DTC B1795 is stored when a malfunction is detected in the occupant detection ECU.

Troubleshoot DTC B1771 first when both DTCs B1771 and B1795 are present.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

B1795

Occupant Classification ECU Malfunction

Occupant detection ECU malfunction.

Occupant detection ECU

HINT:

  • When DTC B1650/32 is stored as a result of troubleshooting the airbag system, perform troubleshooting for DTC B1795 of the occupant classification system.
  • 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

PROCEDURE

1.

CHECK DTC

(a) Turn the power switch on (IG), and wait for at least 60 seconds.

(b) Clear the DTCs.

Click here

Body Electrical > Occupant Detection > Clear DTCs

HINT:

  • First clear the DTCs stored in the occupant detection ECU, and then clear the DTCs stored in the airbag ECU assembly.
  • 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

Body Electrical > Occupant Detection > Trouble Codes

HINT:

DTCs other than DTC B1795 may be output at this time, but they are not related to this check.

DTC B1795 is not output

USE SIMULATION METHOD TO CHECK

DTC B1795 is output

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.

NEXT

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

"Zero Point Calibration is complete." is displayed

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:

 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 malfuncti

 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

 Rear Airbag Sensor

SEE MORE:

 Front Fog Light Circuit

DESCRIPTION Illumination of the front fog lights is controlled by the main body ECU (multiplex network body ECU). WIRING DIAGRAM except Sport Package: for Sport Package: CAUTION / NOTICE / HINT NOTICE: Inspect the fuses for circuits related to this system before performing the following inspect

 Inspection

INSPECTION PROCEDURE 1. INSPECT FRONT NO. 1 SPEAKER ASSEMBLY (a) Measure the resistance according to the value(s) in the table below. Standard Resistance: for 8 Speakers Tester Connection Condition Specified Condition 1 - 2 Always 4 Ω for 10 Speakers Tester Connection Con

© 2016-2024 Copyright www.lexunx.com