Lexus RX (RX 350L, RX450h) 2016-2024 Repair Manual: Lost Communication with Rear Panel LIN (B14B3)

Lexus RX (RX 350L, RX450h) 2016-2024 Repair Manual / Vehicle Interior / Seat / Seat Heater System / Lost Communication with Rear Panel LIN (B14B3)

DESCRIPTION

The refreshing seat switch (for rear side)*1 or rear seat heater switch*2 communicates with the air conditioning amplifier assembly via LIN communication.

If the LIN communication system is malfunctioning, the air conditioning amplifier assembly will not operate even if the refreshing seat switch (for rear side)*1 or rear seat heater switch*2 is operated.

  • *1: w/o Rear No. 2 Seat
  • *2: w/ Rear No. 2 Seat

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

B14B3

Lost Communication with Rear Panel LIN

Lost communication with the refreshing seat switch*1 or rear seat heater switch*2
  • Refreshing seat switch (for rear side)*1
  • Rear seat heater switch*2
  • Air conditioning amplifier assembly
  • Wire harness or connector
  • *1: w/o Rear No. 2 Seat
  • *2: w/ Rear No. 2 Seat

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

Inspect the fuses for circuits related to this system before performing the following procedure.

PROCEDURE

1.

CLEAR DTC

(a) Clear the DTCs.

Click here

Body Electrical > Air Conditioner > Clear DTCs
NEXT

2.

CHECK FOR DTC

(a) Check for DTCs.

Click here

Body Electrical > Air Conditioner > Trouble Codes

OK:

DTC B14B3 is not output.

Result

Proceed to

OK

A

NG (w/o Rear No. 2 Seat)

B

NG (w/ Rear No. 2 Seat)

C
A

USE SIMULATION METHOD TO CHECK

C

GO TO STEP 8

B

3.

CHECK HARNESS AND CONNECTOR (IG POWER SUPPLY - REFRESHING SEAT SWITCH (FOR REAR SIDE) - BODY GROUND)

(a) Disconnect the J15 refreshing seat switch (for rear side) connector.

*a

Front view of wire harness connector

(to Refreshing Seat Switch)

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

Standard Voltage:

Tester Connection

Condition

Specified Condition

J15-1 (IG) - Body ground

Engine switch on (IG)

11 to 14 V

J15-1 (IG) - Body ground

Engine switch off

Below 1 V

Standard Resistance:

Tester Connection

Condition

Specified Condition

J15-5 (E) - Body ground

Always

Below 1 Ω
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

4.

CHECK HARNESS AND CONNECTOR (AIR CONDITIONING AMPLIFIER ASSEMBLY - REFRESHING SEAT SWITCH)

(a) Disconnect the J48 air conditioning amplifier assembly connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

J48-24 (RLIN) - J15-3 (RLIN)

Always

Below 1 Ω

J48-24 (RLIN) or J15-3 (RLIN) - Body ground

Always

10 kΩ or higher
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

5.

REPLACE REFRESHING SEAT SWITCH (FOR REAR SIDE)

(a) Temporarily replace the refreshing seat switch (for rear side) with a new or known good one.

Click here

NEXT

6.

CLEAR DTC

(a) Clear the DTCs.

Click here

Body Electrical > Air Conditioner > Clear DTCs
NEXT

7.

CHECK FOR DTC

(a) Check for DTCs.

Click here

Body Electrical > Air Conditioner > Trouble Codes

OK:

DTC B14B3 is not output.

OK

END (REFRESHING SEAT SWITCH (FOR REAR SIDE) WAS DEFECTIVE)
NG

REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY

8.

CHECK HARNESS AND CONNECTOR (IG POWER SUPPLY - REAR SEAT HEATER SWITCH - BODY GROUND)

(a) Disconnect the V4 rear seat heater switch connector.

*a

Front view of wire harness connector

(to Rear Seat Heater Switch)

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

Standard Voltage:

Tester Connection

Condition

Specified Condition

V4-1 (IG) - Body ground

Engine switch on (IG)

11 to 14 V

V4-1 (IG) - Body ground

Engine switch off

Below 1 V

Standard Resistance:

Tester Connection

Condition

Specified Condition

V4-5 (E) - Body ground

Always

Below 1 Ω
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

9.

CHECK HARNESS AND CONNECTOR (AIR CONDITIONING AMPLIFIER ASSEMBLY - REAR SEAT HEATER SWITCH)

(a) Disconnect the J48 air conditioning amplifier assembly connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

J48-24 (RLIN) - V4-3 (RLIN)

Always

Below 1 Ω

J48-24 (RLIN) or V4-3 (RLIN) - Body ground

Always

10 kΩ or higher
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

10.

REPLACE REAR SEAT HEATER SWITCH

(a) Temporarily rear seat heater switch with a new or known good one.

Click here

NEXT

11.

CLEAR DTC

(a) Clear the DTCs.

Click here

Body Electrical > Air Conditioner > Clear DTCs
NEXT

12.

CHECK FOR DTC

(a) Check for DTCs.

Click here

Body Electrical > Air Conditioner > Trouble Codes

OK:

DTC B14B3 is not output.

OK

END (REAR SEAT HEATER SWITCH WAS DEFECTIVE)
NG

REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY

    Data List / Active Test
    DATA LIST / ACTIVE TEST DATA LIST HINT: Using the Techstream to read the Data List allows the values or states of switches, sensors, actuators and other items to be read without removing any parts. Th ...

    Lost Communication with Front Seat Temperature Adjustment Switch LIN (B14B5)
    DESCRIPTION The refreshing seat switch (for front side) communicates with the air conditioning amplifier assembly via LIN communication. If the LIN communication system is malfunctioning, the air cond ...

    Other materials:

    Lexus RX (RX 350L, RX450h) 2016-2024 Repair Manual > Intelligent Clearance Sonar System: Fr Sensor Initialization Incomplete (C1AF3)
    DESCRIPTION When it is judged that the front sensors have not been initialized, the clearance warning ECU assembly stores DTC C1AF3. DTC No. Detection Item DTC Detection Condition Trouble Area C1AF3 Fr Sensor Initialization Incomplete Front sensor not initialized Initialize fro ...

    Lexus RX (RX 350L, RX450h) 2016-2024 Repair Manual > Automatic Transaxle System: Pressure Control Solenoid "G" Circuit Open (P280713)
    DESCRIPTION Changing gears is performed by the ECM turning the shift solenoid valves SL1, SL2, SL3, SL4 and SL5 on and off. If an open or short occurs in any of the shift solenoid valve circuits, the ECM controls the remaining normal shift solenoid valves to allow the vehicle to be driven. If all of ...

    Lexus RX (RX 350L, RX450h) 2016-{YEAR} Owners Manual

    Lexus RX (RX 350L, RX450h) 2016-{YEAR} Repair Manual

    © 2024 Copyright www.lexusrx.net
    0.0214