B1021

B1017, B1020, B1021 OCCUPANT SENS C/U

Description


DTC B1017, B1020, B1021 [UNIT FAIL] OCCUPANT SENS C/U

Suppresses the deployment of passenger air bag when the condition of passenger seat is empty or child and child-seat. And turns on cut-off telltale lamp when the condition of passenger seat is child-seat and child. In case of malfunction the blinking of the SRS air bag warning lamp report the malfunction to driver and by the on board self-diagnosis system or electro-diagnosis tester CONSULT can detect the cause.

OPERATION

This unit classifies occupant in passenger seat and detects electrical malfunctions in Occupant Classification
System, and transmits malfunction information to air bag control unit.

STRUCTURE

It is integrated into the seat sensor mat and detects the occupants with Occupant Classification System (OCS)
control unit that classifies the occupants.

INSTALLATION

Occupant Classification System (OCS) control unit is installed in the passenger seat cushion.


DTC Logic


DTC DETECTION LOGIC

With CONSULT
DTC No. Index ("SELF-DIAG [CURRENT]"), ("SELF-DIAG [PAST]" or "TROUBLE DIAG RECORD")






DTC CONFIRMATION PROCEDURE (With CONSULT)


1. INSPECTION START

Turn ignition switch ON.
- GO TO 2.

2. CHECK SELF-DIAG RESULT

Check the screen of CONSULT.
Is malfunctioning part detected?
YES- .
NO-INSPECTION END.

DTC CONFIRMATION PROCEDURE (Without CONSULT)

NOTE:
- SRS will not enter diagnosis mode if no malfunction is detected in user mode.

1. INSPECTION START

Turn ignition switch ON.
- GO TO 2.

2. CHECK AIR BAG WARNING LAMP

Check the warning lamp status.
Is malfunctioning part detected?
YES- Testing and Inspection.
NO-INSPECTION END.


Diagnosis Procedure


With CONSULT


WARNING:
- Before servicing, turn ignition switch OFF, disconnect both battery terminals and wait at least 3 minutes. (To discharge backup capacitor.)
- Do not use unspecified tester or other measuring device.

DIAGNOSTIC PROCEDURE


1. CHECK HARNESS CONNECTOR

Check the connection of harness connector.
Is the inspection result normal?
YES- GO TO 2.
NO- Repair or replace harness connectors.

2. CHECK WIRING HARNESS

Check the wiring harness externals.
Is the inspection result normal?
YES- GO TO 3.
NO- Repair or replace wiring harness.

3. CHECK OCCUPANT CLASSIFICATION SYSTEM CONTROL UNIT

1.Replace occupant classification system control unit. (passenger side seat cushion assembly.)
2.Check the screen of CONSULT.
is the inspection result normal?
YES-INSPECTION END.
NO- Check the intermittent incident. Intermittent Incident.