Supplemental Restraint System. Dtc B1635/24 Front Passenger Side Rear Airbag Sensor Circuit Malfunction

Restraints. Lexus Is250, Is220D. Gse20 Ale20

Supplemental Restraint System. Lexus Is250, Is220D. Gse20 Ale20

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

CHECK DTC

CHECK CONNECTION OF CONNECTORS

CHECK FLOOR WIRE (OPEN)

CHECK FLOOR WIRE (SHORT)

CHECK FLOOR WIRE (SHORT TO B+)

CHECK FLOOR WIRE (SHORT TO GROUND)

CHECK FRONT PASSENGER SIDE REAR AIRBAG SENSOR

CHECK FLOOR WIRE (SHORT)

CHECK FLOOR WIRE (SHORT TO GROUND)

CHECK FLOOR WIRE (SHORT TO B+)

CHECK FRONT PASSENGER SIDE - SIDE AIRBAG SENSOR

DTC B1635/24 Front Passenger Side Rear Airbag Sensor Circuit Malfunction

DESCRIPTION

The front passenger side rear airbag sensor circuit consists of the safing sensor, the diagnostic circuit, the lateral deceleration sensor, etc.
If the center airbag sensor assembly receives signals from the lateral deceleration sensor, it determines whether or not the SRS should be activated.
DTC B1635/24 is recorded when a malfunction is detected in the front passenger side rear airbag sensor circuit.

DTC No.	DTC Detection Condition	Trouble Area
B1635/24	The center airbag sensor assembly receives a line short circuit signal, an open circuit signal, a short circuit to ground signal or a short circuit to B+ signal in the front passenger side rear airbag sensor circuit for 2 seconds. Front passenger side - side airbag sensor malfunction Front passenger side rear airbag sensor malfunction Center airbag sensor assembly malfunction	Floor wire Front passenger side - side airbag sensor Front passenger side rear airbag sensor Center airbag sensor assembly

WIRING DIAGRAM

Lexus Is250, Is220D. Gse20 Ale20.Supplemental Restraint System.Airbag System.
Dtc
B1635/24 Front Passenger Side Rear Airbag Sensor Circuit Malfunction

INSPECTION PROCEDURE

1.CHECK DTC

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

Clear the DTCs stored in the memory (Click here).

Turn the engine switch off.

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

Check for DTCs (Click here).
OK:
DTC B1635/24 is not output.
HINT:
Codes other than DTC B1635/24 may be output at this time, but they are not related to this check.

Go to step 2

USE SIMULATION METHOD TO CHECK

2.CHECK CONNECTION OF CONNECTORS

Turn the engine switch off.

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

Check that the connectors are properly connected to the center airbag sensor assembly and the front passenger side rear airbag sensor.
OK:
The connectors are properly connected.

CONNECT CONNECTORS, THEN GO TO STEP 1

OK

3.CHECK FLOOR WIRE (OPEN)

Disconnect the connectors from the center airbag sensor assembly and the front passenger side rear airbag sensor.

Using a service wire, connect P14-8 (BCP+) and P14-11 (BCP-) of connector "B".
NOTICE:
Do not forcibly insert a service wire into the terminals of the connector when connecting.

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

Standard resistance:
LHD:
Tester connection
Condition
Specified condition
P11-4 (BCR+) - P11-3 (BCR-)
Always
Below 1 Ω
RHD:
Tester connection
Condition
Specified condition
Q15-4 (BCL+) - Q15-3 (BCL-)
Always
Below 1 Ω

REPAIR OR REPLACE FLOOR WIRE

OK

4.CHECK FLOOR WIRE (SHORT)

Disconnect the service wire from connector "B".

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

Standard resistance:
LHD:
Tester connection
Condition
Specified condition
P11-4 (BCR+) - P11-3 (BCR-)
Always
1 MΩ or higher
RHD:
Tester connection
Condition
Specified condition
Q15-4 (BCL+) - Q15-3 (BCL-)
Always
1 MΩ or higher

REPAIR OR REPLACE FLOOR WIRE

OK

5.CHECK FLOOR WIRE (SHORT TO B+)

Connect the negative (-) terminal cable to the battery, and wait for at least 2 seconds.

Turn the engine switch on (IG).

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

Standard voltage:
LHD:
Tester connection
Condition
Specified condition
P11-4 (BCR+) - Body ground
Engine switch on (IG)
Below 1 V
P11-3 (BCR-) - Body ground
Engine switch on (IG)
Below 1 V
RHD:
Tester connection
Condition
Specified condition
Q15-4 (BCL+) - Body ground
Engine switch on (IG)
Below 1 V
Q15-3 (BCL-) - Body ground
Engine switch on (IG)
Below 1 V

REPAIR OR REPLACE FLOOR WIRE

OK

6.CHECK FLOOR WIRE (SHORT TO GROUND)

Turn the engine switch off.

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

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

Standard resistance:
LHD:
Tester connection
Condition
Specified condition
P11-4 (BCR+) - Body ground
Always
1 MΩ or higher
P11-3 (BCR-) - Body ground
Always
1 MΩ or higher
RHD:
Tester connection
Condition
Specified condition
Q15-4 (BCL+) - Body ground
Always
1 MΩ or higher
Q15-3 (BCL-) - Body ground
Always
1 MΩ or higher

REPAIR OR REPLACE FLOOR WIRE

OK

7.CHECK FRONT PASSENGER SIDE REAR AIRBAG SENSOR

Connect the connectors to the center airbag sensor assembly.

Interchange the front passenger side rear airbag sensor with the driver side rear airbag senor and connect the connectors to them.

Connect the negative (-) terminal cable to the battery, and wait for at least 2 seconds.

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

Clear the DTCs stored in the memory (Click here).

Turn the engine switch off.

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

Check for DTCs (Click here).
Result:
Result
Proceed to
DTC B1635/24 is output.
A
DTC B1630/23 is output.
B
DTC B1630/23 and B1635/24 are not output.
C
HINT:
Codes other than DTC B1630/23 and B1635/24 may be output at this time, but they are not related to this check.

Go to step 8

REPLACE FRONT PASSENGER SIDE REAR AIRBAG SENSOR

USE SIMULATION METHOD TO CHECK

8.CHECK FLOOR WIRE (SHORT)

Turn the engine switch off.

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

Return the driver side rear airbag sensor and front passenger side rear airbag sensor to their original positions and connect the connectors to them.

Disconnect the connectors from the front passenger side - side airbag sensor and front passenger side rear airbag sensor.

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

Standard resistance:
LHD:
Tester connection
Condition
Specified condition
P11-1 (BBR+) - P11-2 (BBR-)
Always
1 MΩ or higher
RHD:
Tester connection
Condition
Specified condition
Q15-1 (BBL+) - Q15-2 (BBL-)
Always
1 MΩ or higher

REPAIR OR REPLACE FLOOR WIRE

OK

9.CHECK FLOOR WIRE (SHORT TO GROUND)

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

Standard resistance:
LHD:
Tester connection
Condition
Specified condition
P11-1 (BBR+) - Body ground
Always
1 MΩ or higher
P11-2 (BBR-) - Body ground
Always
1 MΩ or higher
RHD:
Tester connection
Condition
Specified condition
Q15-1 (BBL+) - Body ground
Always
1 MΩ or higher
Q15-2 (BBL-) - Body ground
Always
1 MΩ or higher

REPAIR OR REPLACE FLOOR WIRE

OK

10.CHECK FLOOR WIRE (SHORT TO B+)

Connect the negative (-) terminal cable to the battery, and wait for at least 2 seconds.

Turn the engine switch on (IG).

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

Standard voltage:
LHD:
Tester connection
Condition
Specified condition
P11-1 (BBR+) - Body ground
Engine switch on (IG)
Below 1 V
P11-2 (BBR-) - Body ground
Engine switch on (IG)
Below 1 V
RHD:
Tester connection
Condition
Specified condition
Q15-1 (BBL+) - Body ground
Engine switch on (IG)
Below 1 V
Q15-2 (BBL-) - Body ground
Engine switch on (IG)
Below 1 V

REPAIR OR REPLACE FLOOR WIRE

OK

11.CHECK FRONT PASSENGER SIDE - SIDE AIRBAG SENSOR

Turn the engine switch off.

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

Connect the connector to the front passenger side rear airbag sensor.

Interchange the front passenger side - side airbag sensor with the driver side - side airbag sensor and connect the connectors to them.

Connect the negative (-) terminal cable to the battery, and wait for at least 2 seconds.

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

Clear the DTCs stored in the memory (Click here).

Turn the engine switch off.

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

Check for DTCs (Click here).
Result:
Result
Proceed to
DTC B1635/24 is output.
A
DTC B1630/23 is output.
B
DTC B1630/23 and B1635/24 are not output.
C
HINT:
Codes other than DTC B1630/23 and B1635/24 may be output at this time, but they are not related to this check.

REPLACE CENTER AIRBAG SENSOR ASSEMBLY

REPLACE FRONT PASSENGER SIDE - SIDE AIRBAG SENSOR

USE SIMULATION METHOD TO CHECK

Tester connection	Condition	Specified condition
P11-4 (BCR+) - P11-3 (BCR-)	Always	Below 1 Ω

Result	Proceed to
DTC B1635/24 is output.	A
DTC B1630/23 is output.	B
DTC B1630/23 and B1635/24 are not output.	C

Tester connection	Condition	Specified condition
Q15-4 (BCL+) - Q15-3 (BCL-)	Always	1 MΩ or higher

Tester connection	Condition	Specified condition
Q15-4 (BCL+) - Body ground	Engine switch on (IG)	Below 1 V
Q15-3 (BCL-) - Body ground	Engine switch on (IG)	Below 1 V