Toyota Venza: Short in Driver Side Knee Airbag Squib Circuit (B1860/64-B1863/64)

Toyota Venza Service Manual / Supplemental Restraint Systems / Airbag System / Short in Driver Side Knee Airbag Squib Circuit (B1860/64-B1863/64)

DESCRIPTION

The driver side knee airbag squib circuit consists of the center airbag sensor assembly and driver side knee airbag assembly.

The center airbag sensor assembly uses this circuit to deploy the airbag when deployment conditions are met.

These DTCs are stored when a malfunction is detected in the driver side knee airbag squib circuit.

DTC No.	DTC Detection Condition	Trouble Area
B1860/64	The center airbag sensor assembly receives a line short circuit signal in the driver side knee airbag squib circuit during primary check. Driver side knee airbag squib malfunction Center airbag sensor assembly malfunction	Instrument panel wire Driver side knee airbag assembly (Driver side knee airbag squib) Center airbag sensor assembly
B1861/64	The center airbag sensor assembly receives an open circuit signal in the driver side knee airbag squib circuit. Driver side knee airbag squib malfunction Center airbag sensor assembly malfunction	Instrument panel wire Driver side knee airbag assembly (Driver side knee airbag squib) Center airbag sensor assembly
B1862/64	The center airbag sensor assembly receives a short circuit to ground signal in the driver side knee airbag squib circuit. Driver side knee airbag squib malfunction Center airbag sensor assembly malfunction	Instrument panel wire Driver side knee airbag assembly (Driver side knee airbag squib) Center airbag sensor assembly
B1863/64	The center airbag sensor assembly receives a short circuit to B+ signal in the driver side knee airbag squib circuit. Driver side knee airbag squib malfunction Center airbag sensor assembly malfunction	Instrument panel wire Driver side knee airbag assembly (Driver side knee airbag squib) Center airbag sensor assembly

WIRING DIAGRAM

CAUTION / NOTICE / HINT

HINT:

Perform the simulation method by selecting check mode (Signal Check) using the Techstream (See page ).
After selecting check mode (Signal Check), perform the simulation method by wiggling each connector of the airbag system or driving the vehicle on a city or rough road (See page ).

PROCEDURE

1.	CHECK CONNECTORS

(a) Turn the ignition switch off.

(b) Disconnect the cable from the negative (-) battery terminal, and wait for at least 90 seconds.

(c) Check that the connectors are properly connected to the driver side knee airbag assembly and center airbag sensor assembly.

OK:

The connectors are properly connected.

HINT:

If the connectors are not connected securely, reconnect the connectors and proceed to the next inspection.

(d) Disconnect the connectors from the driver side knee airbag assembly and center airbag sensor assembly.

(e) Check that the terminals of the connectors are not damaged.

OK:

The terminals are not deformed or damaged.

(f) Check that the instrument panel wire connector (on the driver side knee airbag assembly side) is not damaged.

OK:

The lock button is not disengaged, and the claw of the lock is not deformed or damaged.

(g) Check that the short spring for the instrument panel wire with the activation prevention mechanism are not deformed or damaged.

OK:

The short spring is not deformed or damaged.

Text in Illustration

*1	Driver Side Knee Airbag Squib
*2	Center Airbag Sensor Assembly
*3	Instrument Panel Wire

REPLACE INSTRUMENT PANEL WIRE

2.	CHECK DRIVER SIDE KNEE AIRBAG ASSEMBLY (DRIVER SIDE KNEE AIRBAG SQUIB)

(a) Connect the connector to the center airbag sensor assembly.

(b) Connect SST (resistance 2.1 Ω) to connector C.

CAUTION:

Never connect an electrical tester to the driver side knee airbag assembly (driver side knee airbag squib) for measurement, as this may lead to a serious injury due to airbag deployment.

NOTICE:

Do not forcibly insert SST into the terminals of the connector when connecting.
Insert SST straight into the terminals of the connector.

SST: 09843-18061

(d) Turn the ignition switch to ON, and wait for at least 60 seconds.

(e) Clear the DTCs stored in memory (See page ).

(f) Turn the ignition switch off.

(g) Turn the ignition switch to ON, and wait for at least 60 seconds.

(h) Check for DTCs (See page ).

OK:

DTC B1860, B1861, B1862, B1863 or 64 is not output.

Text in Illustration

*1	Driver Side Knee Airbag Squib
*2	Center Airbag Sensor Assembly
*3	Front view of wire harness connector (to Driver Side Knee Airbag Assembly)
*4	Connector C

HINT:

Codes other than DTCs B1860, B1861, B1862, B1863 and 64 may be output at this time, but they are not related to this check.

REPLACE DRIVER SIDE KNEE AIRBAG ASSEMBLY

3.	CHECK INSTRUMENT PANEL WIRE (DRIVER SIDE KNEE AIRBAG SQUIB CIRCUIT)

(a) Turn the ignition switch off.

(b) Disconnect the cable from the negative (-) battery terminal, and wait for at least 90 seconds.

(d) Disconnect the instrument panel wire from the center airbag sensor assembly.

(e) Check for a short to B+ in the circuit.

(1) Connect the cable to the negative (-) battery terminal.

(2) Turn the ignition switch to ON.

(3) Measure the voltage according to the value(s) in the table below.

Standard Voltage:

Tester Connection	Switch Condition	Specified Condition
D9-1 (DK+) - Body ground	Ignition switch ON	Below 1 V
D9-2 (DK-) - Body ground	Ignition switch ON	Below 1 V

(f) Check for an open in the circuit.

(1) Turn the ignition switch off.

(2) Disconnect the cable from the negative (-) battery terminal, and wait for at least 90 seconds.

(3) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection	Condition	Specified Condition
D9-1 (DK+) - D9-2 (DK-)	Always	Below 1 Ω

(g) Check for a short to ground in the circuit.

(1) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection	Condition	Specified Condition
D9-1 (DK+) - Body ground	Always	1 MΩ or higher
D9-2 (DK-) - Body ground	Always	1 MΩ or higher

(h) Check for a short in the circuit.

(1) Release the activation prevention mechanism built into connector B (See page ).

(2) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection	Condition	Specified Condition
D9-1 (DK+) - D9-2 (DK-)	Always	1 MΩ or higher

Text in Illustration

*1	Driver Side Knee Airbag Squib
*2	Center Airbag Sensor Assembly
*3	Instrument Panel Wire
*4	Front view of wire harness connector (to Driver Side Knee Airbag Assembly)
*5	Connector C

REPLACE INSTRUMENT PANEL WIRE

4.	CHECK CENTER AIRBAG SENSOR ASSEMBLY

(a) Restore the released activation prevention mechanism of connector B to the original condition.

(b) Connect the connectors to the driver side knee airbag assembly and center airbag sensor assembly.

(d) Turn the ignition switch to ON, and wait for at least 60 seconds.

(e) Clear the DTCs stored in memory (See page ).

(f) Turn the ignition switch off.

(g) Turn the ignition switch to ON, and wait for at least 60 seconds.

(h) Check for DTCs (See page ).

OK:

DTC B1860, B1861, B1862, B1863 or 64 is not output.

Text in Illustration

*1	Driver Side Knee Airbag Squib
*2	Center Airbag Sensor Assembly

HINT:

Codes other than DTCs B1860, B1861, B1862, B1863 and 64 may be output at this time, but they are not related to this check.

USE SIMULATION METHOD TO CHECK

REPLACE CENTER AIRBAG SENSOR ASSEMBLY

Short in Curtain Shield Squib LH Circuit (B1835/58-B1838/58)

DESCRIPTION The curtain shield squib LH circuit consists of the center airbag sensor assembly and curtain shield airbag assembly LH. The center airbag sensor assembly uses this circuit to deploy t ...

Short in Front Pretensioner Squib RH Circuit (B1900/73-B1903/73)

DESCRIPTION The front pretensioner squib RH circuit consists of the center airbag sensor assembly and front seat outer belt assembly RH. The center airbag sensor assembly uses this circuit to depl ...

Other materials about Toyota Venza:

Lost Communication with Power Source Control (B278C)
DESCRIPTION This DTC is stored when LIN communication between the certification ECU (smart key ECU assembly) and power management control ECU stops for more than 10 seconds. DTC Code DTC Detection Condition Trouble Area ...

Terminals Of Ecu
TERMINALS OF ECU 1. CHECK AIR CONDITIONING AMPLIFIER ASSEMBLY (a) Disconnect the D47 air conditioning amplifier assembly connector. (b) Measure the voltage and resistance according to the value(s) in the table below. HINT: Measure the values on the wi ...

Lost Communication with AFS LIN (B124D)
DESCRIPTION The DTC is stored when the main body ECU (driver side junction block assembly) detects malfunctions in the LIN communication system. DTC No. DTC Detection Condition Trouble Area B124D ...