Lexus RX (RX 350L, RX450h) 2016-2024 Repair Manual: 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

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