Lexus RX (RX 350L, RX450h) 2016-2025 Repair Manual: Sensor (Motor) Failure (B2341,B2344)

Lexus RX (RX 350L, RX450h) 2016-2025 Repair Manual / Vehicle Exterior / Sliding Roof / Convertible / Panoramic Moon Roof System / Sensor (Motor) Failure (B2341,B2344)

DESCRIPTION

When the sliding roof ECU (sliding roof drive gear assembly) or roof sunshade ECU (sliding roof drive gear assembly) detects a motor malfunction and the sliding roof and roof sunshade operation is stopped, DTC B2341 is stored.

When the sliding roof ECU (sliding roof drive gear assembly) or roof sunshade ECU (sliding roof drive gear assembly) detects a gear position malfunction and the sliding roof and roof sunshade operation is stopped, DTC B2344 is stored.

Sliding Roof

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

B2341

Sensor (Motor) Failure

Sensor (motor) failure (When the sliding roof ECU (sliding roof drive gear assembly) enters fail-safe mode due to a problem with the motor)
  • Sliding roof ECU (Sliding roof drive gear assembly)
  • Map light assembly
  • Wire harness or connector

B2344

Position Failure

Position failure (When the sliding roof ECU (sliding roof drive gear assembly) enters fail-safe mode due to a problem with the gear position)
  • Sliding roof ECU (Sliding roof drive gear assembly)
  • Map light assembly
  • Wire harness or connector
Sliding Sunshade

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

B2341

Sensor (Motor) Failure

Sensor (motor) failure (When the roof sunshade ECU (sliding roof drive gear assembly) enters fail-safe mode due to a problem with the motor)
  • Roof sunshade ECU (Sliding roof drive gear assembly)
  • Map light assembly
  • Wire harness or connector

B2344

Position Failure

Position failure (When the roof sunshade ECU (sliding roof drive gear assembly) enters fail-safe mode due to a problem with the gear position)
  • Roof sunshade ECU (Sliding roof drive gear assembly)
  • Map light assembly
  • Wire harness or connector

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

  • If the sliding roof ECU (sliding roof drive gear assembly) or roof sunshade ECU (sliding roof drive gear assembly) is removed and reinstalled or replaced, the sliding roof ECU (sliding roof drive gear assembly) or roof sunshade ECU (sliding roof drive gear assembly) must be initialized.

    Click here

  • The panoramic moon roof system uses the LIN communication system. First, confirm that there are no malfunctions in the LIN communication system. Refer to How to Proceed with Troubleshooting.

    Click here

  • DTCs B2341 and B2344 are stored in the sliding roof ECU (sliding roof drive gear assembly) and roof sunshade ECU (sliding roof drive gear assembly).

PROCEDURE

1.

CHECK FOR DTC

(a) Clear the DTCs.

Click here

Body Electrical > Sliding Roof > Clear DTCs Body Electrical > Sliding Sunshade > Clear DTCs

(b) Check for DTCs.

Click here

Body Electrical > Sliding Roof > Trouble Codes Body Electrical > Sliding Sunshade > Trouble Codes

OK:

DTCs B2341 and B2344 are not output.

OK

USE SIMULATION METHOD TO CHECK

NG

2.

CHECK DTC OUTPUT

(a) Check the parts from which this DTC has been output.

Result

Proceed to

DTC output from sliding roof ECU (sliding roof drive gear assembly)

A

DTC output from roof sunshade ECU (sliding roof drive gear assembly)

B
B

GO TO STEP 9

A

3.

CHECK SLIDING ROOF OPERATION

(a) Check the sliding roof auto operation function.

Click here

OK:

Auto operation function operates normally.

NG

GO TO STEP 5

OK

4.

CHECK DTC OUTPUT

(a) Clear the DTCs.

Click here

Body Electrical > Sliding Roof > Clear DTCs

(b) Check for DTCs.

Body Electrical > Sliding Roof > Trouble Codes

OK:

DTCs B2341 and B2344 are not output.

OK

USE SIMULATION METHOD TO CHECK

NG

REPLACE SLIDING ROOF ECU (SLIDING ROOF DRIVE GEAR ASSEMBLY)

5.

INITIALIZE SLIDING ROOF ECU (SLIDING ROOF DRIVE GEAR ASSEMBLY)

(a) Check that the sliding roof ECU (sliding roof drive gear assembly) can be initialized.

Click here

OK:

Sliding roof ECU (sliding roof drive gear assembly) can be initialized.

NG

GO TO STEP 7

OK

6.

CHECK DTC OUTPUT

(a) Clear the DTCs.

Click here

Body Electrical > Sliding Roof > Clear DTCs

(b) Check for DTCs.

Body Electrical > Sliding Roof > Trouble Codes

OK:

DTCs B2341 and B2344 are not output.

OK

END (MALFUNCTION DUE TO INITIALIZATION FAILURE)
NG

REPLACE SLIDING ROOF ECU (SLIDING ROOF DRIVE GEAR ASSEMBLY)

7.

CHECK HARNESS AND CONNECTOR (SLIDING ROOF ECU (SLIDING ROOF DRIVE GEAR ASSEMBLY) - MAP LIGHT ASSEMBLY AND BODY GROUND)

(a) Disconnect the U2 sliding roof ECU (sliding roof drive gear assembly) connector.

(b) Disconnect the U11 map light assembly connector.

(c) Disconnect the w1 roof sunshade ECU (sliding roof drive gear assembly) connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

U2-8 (CLS) - U11-12 (CLS)

Always

Below 1 Ω

U2-8 (CLS) or U11-12 (CLS) - Body ground

Always

10 kΩ or higher

U2-10 (OPN) - U11-11 (OPN)

Always

Below 1 Ω

U2-10 (OPN) or U11-11 (OPN) - Body ground

Always

10 kΩ or higher

U2-4 (TILT) - U11-7 (B)

Always

Below 1 Ω

U2-4 (TILT) or U11-7 (B) - Body ground

Always

10 kΩ or higher

U2-5 (OPN) - U11-23 (OPN)

Always

Below 1 Ω

U2-5 (OPN) or U11-23 (OPN) - Body ground

Always

10 kΩ or higher

U2-9 (CLS) - U11-24 (DOWN)

Always

Below 1 Ω

U2-9 (CLS) or U11-24 (DOWN) - Body ground

Always

10 kΩ or higher

U2-2 (E) - Body ground

Always

Below 1 Ω

U11-19 (GND) - Body ground

Always

Below 1 Ω
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

8.

INSPECT MAP LIGHT ASSEMBLY

(a) Remove the map light assembly.

Click here

(b) Inspect the map light assembly.

Click here

OK

REPLACE SLIDING ROOF ECU (SLIDING ROOF DRIVE GEAR ASSEMBLY)

NG

REPLACE MAP LIGHT ASSEMBLY

9.

CHECK ROOF SUNSHADE OPERATION

(a) Check the roof sunshade auto operation function.

Click here

OK:

Auto operation function operates normally.

NG

GO TO STEP 11

OK

10.

CHECK DTC OUTPUT

(a) Clear the DTCs.

Click here

Body Electrical > Sliding Sunshade > Clear DTCs

(b) Check for DTCs.

Body Electrical > Sliding Sunshade > Trouble Codes

OK:

DTCs B2341 and B2344 are not output.

OK

USE SIMULATION METHOD TO CHECK

NG

REPLACE ROOF SUNSHADE ECU (SLIDING ROOF DRIVE GEAR ASSEMBLY)

11.

INITIALIZE ROOF SUNSHADE ECU (SLIDING ROOF DRIVE GEAR ASSEMBLY)

(a) Check that the roof sunshade ECU (sliding roof drive gear assembly) can be initialized.

Click here

OK:

Roof sunshade ECU (sliding roof drive gear assembly) can be initialized.

NG

GO TO STEP 13

OK

12.

CHECK DTC OUTPUT

(a) Clear the DTCs.

Click here

Body Electrical > Sliding Sunshade > Clear DTCs

(b) Check for DTCs.

Body Electrical > Sliding Sunshade > Trouble Codes

OK:

DTCs B2341 and B2344 are not output.

OK

END (MALFUNCTION DUE TO INITIALIZATION FAILURE)
NG

REPLACE ROOF SUNSHADE ECU (SLIDING ROOF DRIVE GEAR ASSEMBLY)

13.

CHECK HARNESS AND CONNECTOR (ROOF SUNSHADE ECU (SLIDING ROOF DRIVE GEAR ASSEMBLY) - MAP LIGHT ASSEMBLY AND BODY GROUND)

(a) Disconnect the w1 roof sunshade ECU (sliding roof drive gear assembly) connector.

(b) Disconnect the U11 map light assembly connector.

(c) Disconnect the U2 sliding roof ECU (sliding roof drive gear assembly) connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

w1-8 (CLS) - U11-12 (CLS)

Always

Below 1 Ω

w1-8 (CLS) or U11-12 (CLS) - Body ground

Always

10 kΩ or higher

w1-10 (OPN) - U11-11 (OPN)

Always

Below 1 Ω

w1-10 (OPN) or U11-11 (OPN) - Body ground

Always

10 kΩ or higher

w1-4 (VENT) - U11-7 (B)

Always

Below 1 Ω

w1-4 (VENT) or U11-7 (B) - Body ground

Always

10 kΩ or higher

w1-5 (OPN) - U11-23 (UP)

Always

Below 1 Ω

w1-5 (OPN) or U11-23 (UP) - Body ground

Always

10 kΩ or higher

w1-9 (CLS) - U11-24 (DOWN)

Always

Below 1 Ω

w1-9 (CLS) or U11-24 (DOWN) - Body ground

Always

10 kΩ or higher

w1-2 (E) - Body ground

Always

Below 1 Ω

U11-19 (GND) - Body ground

Always

Below 1 Ω
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

14.

INSPECT MAP LIGHT ASSEMBLY

(a) Remove the map light assembly.

Click here

(b) Inspect the map light assembly.

Click here

OK

REPLACE ROOF SUNSHADE ECU (SLIDING ROOF DRIVE GEAR ASSEMBLY)

NG

REPLACE MAP LIGHT ASSEMBLY

    Diagnostic Trouble Code Chart
    DIAGNOSTIC TROUBLE CODE CHART Panoramic Moon Roof System DTC No. Detection Item Link B2341 Sensor (Motor) Failure B2341 Sensor (Motor) Failure B2342 Switch Failure ...

    Switch Failure (B2342)
    DESCRIPTION This DTC is stored when the sliding roof ECU (sliding roof drive gear assembly) or roof sunshade ECU (sliding roof drive gear assembly) detects that the map light assembly is stuck for 30 ...

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