Lexus RX (RX 350L, RX450h) 2016-2025 Repair Manual: Abnormal Height Sensor Data at Initialization (B2452)

Lexus RX (RX 350L, RX450h) 2016-2025 Repair Manual / Vehicle Exterior / Lighting (ext) / Lighting System (w/ Automatic Headlight Beam Level Control System) / Abnormal Height Sensor Data at Initialization (B2452)

DESCRIPTION

The No. 1 headlight ECU sub-assembly LH stores this DTC if the value from the rear height control sensor sub-assembly RH is out of range when performing initialization of the No. 1 headlight ECU sub-assembly LH, such as when the vehicle is not level or jacked up.

for Multiple Beam Headlight

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

DTC Output from

B2452

Abnormal Height Sensor Data at Initialization
  • The engine switch is on (IG).
  • Abnormal rear height control sensor sub-assembly RH value detected during initialization
  • -
  • Vehicle condition when initializing
  • Rear height control sensor sub-assembly RH
  • Harness or connector
  • No. 1 headlight ECU sub-assembly LH

AFS
for Single Beam Headlight

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

DTC Output from

B2452

Abnormal Height Sensor Data at Initialization
  • The engine switch is on (IG).
  • Abnormal rear height control sensor sub-assembly RH value detected during initialization
  • -
  • Vehicle condition when initializing
  • Rear height control sensor sub-assembly RH
  • Harness or connector
  • No. 1 headlight ECU sub-assembly LH

HL AutoLeveling

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

  • If the No. 1 headlight ECU sub-assembly LH has been replaced, it is necessary to synchronize the vehicle information and initialize the No. 1 headlight ECU sub-assembly LH.

    Click here

  • If the headlight assembly LH has been replaced, it is necessary to synchronize the vehicle information and initialize the No. 1 headlight ECU sub-assembly LH.*

    Click here

  • If any of the following are performed, it is necessary to initialize the No. 1 headlight ECU sub-assembly LH.

    Click here

    • Replacement of the rear height control sensor sub-assembly RH
    • Removal/installation of the rear height control sensor sub-assembly RH
    • Work that changes the vehicle height such as replacement of suspension components
  • When replacing the No. 1 headlight ECU sub-assembly LH, always replace it with a new one. If a No. 1 headlight ECU sub-assembly LH which was installed to another vehicle is used, the information stored in it will not match the information from the vehicle and a DTC may be stored.
  • When replacing the headlight assembly LH, always replace it with a new one. If a headlight assembly LH which was installed to another vehicle is used, the information stored in it will not match the information from the vehicle and a DTC may be stored.*
    • *: for TMMC Made

PROCEDURE

1.

INITIALIZATION NO. 1 HEADLIGHT ECU SUB-ASSEMBLY LH

(a) Perform initialization of the No. 1 headlight ECU sub-assembly LH.

Click here

NEXT

2.

CONFIRM MODEL

(a) Choose the model to be inspected.

Result

Proceed to

for Multiple Beam Headlight

A

for Single Beam Headlight

B
B

GO TO STEP 5

A

3.

CLEAR DTC

(a) Connect the Techstream to the DLC3.

(b) Turn the engine switch on (IG).

(c) Turn the Techstream on.

(d) Enter the following menus: Body Electrical / AFS / Trouble Codes.

(e) Clear the DTCs.

Body Electrical > AFS > Clear DTCs
NEXT

4.

CHECK FOR DTC

(a) Connect the Techstream to the DLC3.

(b) Turn the engine switch on (IG).

(c) Turn the Techstream on.

(d) Enter the following menus: Body Electrical / AFS / Trouble Codes.

(e) Check for DTCs.

Body Electrical > AFS > Trouble Codes

OK:

DTC B2452 is not output.

OK

END (INITIALIZATION WAS NOT COMPLETED)
NG

GO TO STEP 7

5.

CLEAR DTC

(a) Connect the Techstream to the DLC3.

(b) Turn the engine switch on (IG).

(c) Turn the Techstream on.

(d) Enter the following menus: Body Electrical / HL AutoLeveling / Trouble Codes.

(e) Clear the DTCs.

Body Electrical > HL AutoLeveling > Clear DTCs
NEXT

6.

CHECK FOR DTC

(a) Connect the Techstream to the DLC3.

(b) Turn the engine switch on (IG).

(c) Turn the Techstream on.

(d) Enter the following menus: Body Electrical / HL AutoLeveling / Trouble Codes.

(e) Check for DTCs.

Body Electrical > HL AutoLeveling > Trouble Codes

OK:

DTC B2452 is not output.

OK

END (INITIALIZATION WAS NOT COMPLETED)
NG

7.

CHECK REAR HEIGHT CONTROL SENSOR SUB-ASSEMBLY RH

(a) Check the installation condition of the rear height control sensor sub-assembly RH.

OK:

Rear height control sensor sub-assembly RH is installed correctly.

NG

INSTALL PARTS CORRECTLY

OK

8.

INSPECT REAR HEIGHT CONTROL SENSOR SUB-ASSEMBLY RH

(a) Remove the rear height control sensor sub-assembly RH.

Click here

(b) Inspect the rear height control sensor sub-assembly RH.

Click here

NG

REPLACE REAR HEIGHT CONTROL SENSOR SUB-ASSEMBLY RH

OK

9.

CHECK HARNESS AND CONNECTOR (REAR HEIGHT CONTROL SENSOR SUB-ASSEMBLY RH - NO. 1 HEADLIGHT ECU SUB-ASSEMBLY LH)

(a) Disconnect the A49 No. 1 headlight ECU sub-assembly LH connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

T3-3 (SHB) - A49-16 (SBR)

Always

Below 1 Ω

T3-2 (SHRR) - A49-17 (SHRL)

Always

Below 1 Ω

T3-1 (SHG) - A49-15 (SGR)

Always

Below 1 Ω

T3-3 (SHB) or A49-16 (SBR) - Body ground

Always

10 kΩ or higher

T3-2 (SHRR) or A49-17 (SHRL) - Body ground

Always

10 kΩ or higher
OK

REPLACE NO. 1 HEADLIGHT ECU SUB-ASSEMBLY LH

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
    Variation Code not Written (B2451)
    DESCRIPTION The No. 1 headlight ECU sub-assembly LH stores this DTC if the vehicle specifications have not been stored. DTC No. Detection Item DTC Detection Condition Trouble Area DTC Outpu ...

    Left Headlight ECU Variation Error (B2456)
    DESCRIPTION This DTC is stored if the No. 1 headlight ECU sub-assembly LH for another destination is installed. DTC No. Detection Item DTC Detection Condition Trouble Area DTC Output from ...

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