Lexus RX (RX 350L, RX450h) 2016-2024 Repair Manual: Left Front Wheel Speed Sensor Circuit Intermittent (C05001F)

DESCRIPTION

The speed sensor detects wheel speed and sends the appropriate signals to the skid control ECU (brake actuator assembly). These signals are used for brake control.

Speed sensor rotors have rows of alternating N and S magnetic poles, and their magnetic fields change when the rotors turn.

Each speed sensor detects that magnetic change and sends a pulse signal to the skid control ECU (brake actuator assembly).

HINT:

When the connectors between the speed sensor and skid control ECU (brake actuator assembly) are connected, the following waveform is output.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area
C05001F	Left Front Wheel Speed Sensor Circuit Intermittent	Any of the following is detected: When the +BS terminal voltage is 17.4 V or less, an open in the sensor signal circuit of a malfunctioning area occurs 255 times or more. When the +BS terminal voltage is 17.4 V or less at a vehicle speed of 20 km/h (12 mph) or more, noise occurs in the sensor signals of a malfunctioning wheel 75 times or more within 5 seconds. When the +BS terminal voltage is 17.4 V or less at a vehicle speed of 10 km/h (6 mph) or more, noise occurs once per rotor rotation for 15 seconds or more.	Front speed sensor LH Front skid control sensor wire LH* Speed sensor installation Wire harness and connector Front speed sensor rotor LH (front axle hub sub-assembly LH) Skid control ECU (brake actuator assembly)

*: w/ AVS

DTC Detection Conditions : C05001F

		Vehicle Condition
		Pattern 1	Pattern 2	Pattern 3
Diagnosis Condition	When the +BS terminal voltage is 17.4 V or less	○	-	-
	When the +BS terminal voltage is 17.4 V or less at a vehicle speed of 10 km/h (6 mph) or more	-	-	○
	When the +BS terminal voltage is 17.4 V or less at a vehicle speed of 20 km/h (12 mph) or more	-	○	-
Malfunction Status	An open in the sensor signal circuit of a malfunctioning area occurs 255 times or more	○	-	-
	Noise occurs in the sensor signals of a malfunctioning wheel 75 times or more within 5 seconds	-	○	-
	Noise occurs once per rotor rotation	-	-	○
Detection Time		-	-	15 seconds or more
Number of Trips		1 trip	1 trip	1 trip

HINT:

DTC will be output when conditions for any of the patterns in the table above are met.

WIRING DIAGRAM

w/o AVS w/ AVS

CAUTION / NOTICE / HINT

PROCEDURE

1.	READ VALUE USING TECHSTREAM (MOMENTARY INTERRUPTION)

(a) Connect the Techstream to the DLC3.

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

(c) Enter the following menus: Chassis / Brake/EPB / Data List.

Chassis > Brake/EPB > Data List

Tester Display	Measurement Item	Range	Normal Condition	Diagnostic Note
FL Speed Sensor Voltage Open	Front speed sensor LH voltage open detection	Under intermittent / Normal	Under intermittent: Momentary interruption detected Normal: Momentary interruption not detected	-

Chassis > Brake/EPB > Data List

Tester Display
FL Speed Sensor Voltage Open

(d) Select the line graph display.

(e) Check for any momentary interruption in the wire harness and connector.

Click here

OK:

Normal (There are no momentary interruptions.)

NOTICE:

Perform the above inspection before removing the sensor and connector.

NG

GO TO STEP 5

OK

2.	READ VALUE USING TECHSTREAM (FL WHEEL SPEED)

(a) Enter the following menus: Chassis / Brake/EPB / Data List.

Chassis > Brake/EPB > Data List

Tester Display	Measurement Item	Range	Normal Condition	Diagnostic Note
FL Wheel Speed	Front wheel speed sensor LH reading	Min.: 0.0 km/h (0.0 mph) Max.: 6553.5 km/h (4072 mph)	Vehicle stopped: 0.0 km/h (0.0 mph)	When driving at constant speed: No large fluctuations

Chassis > Brake/EPB > Data List

Tester Display
FL Wheel Speed

(b) Start the engine.

(c) Perform a road test.

(d) Check the speed value output from the speed sensor displayed on the Techstream.

HINT:

Factors that affect the indicated vehicle speed include tire size, tire pressure, and tire wear. The speed indicated on the speedometer has an allowable margin of error. This can be tested using a speedometer tester (calibrated chassis dynamometer). For details about testing and the margin of error, see the reference chart.

Click here

OK:

The speed value output from the speed sensor displayed on the Techstream is similar to the speed indicated on the speedometer.

NG

GO TO STEP 5

OK

3.

CLEAR DTC

(a) Operate the Techstream to clear the codes. Enter the following menus: Chassis / Brake/EPB / Trouble Codes.

Chassis > Brake/EPB > Clear DTCs

(b) Press the DTC clear button.

(c) Turn the engine switch off.

NEXT

4.	RECONFIRM DTC

(a) Start the engine.

(b) Perform a road test.

(c) Read the DTCs following the prompts on the Techstream. Enter the following menus: Chassis / Brake/EPB / Trouble Codes.

Chassis > Brake/EPB > Trouble Codes

(d) Check if the same DTC is output.

Result	Proceed to
DTC C05001F is not output.	A
DTC C05001F is output.	B

A

USE SIMULATION METHOD TO CHECK

B

REPLACE BRAKE ACTUATOR ASSEMBLY

5.	CHECK FRONT SPEED SENSOR LH INSTALLATION

(a) Turn the engine switch off.

*1 Front Speed Sensor LH *a Correct *b Incorrect *c 8.5 Nm *d No clearance

(b) Check the front speed sensor LH installation.

OK:

There is no clearance between the front speed sensor LH and steering knuckle.

The installation bolt is tightened properly.

Torque

8.5 N*m (87 kgf*cm, 75 in.*lbf)

NG

REINSTALL OR REPLACE FRONT SPEED SENSOR LH

OK

6.	CHECK FRONT SPEED SENSOR LH AND FRONT SPEED SENSOR ROTOR LH (CHECK FOR FOREIGN MATTER)

(a) Remove the front speed sensor LH and the component with the front speed sensor rotor LH.

for front speed sensor LH: Click here

for front speed sensor rotor LH: Click here

(b) Check the front speed sensor LH tip and front speed sensor rotor LH.

OK:

No scratches, oil, or foreign matter on the front speed sensor LH tip and front speed sensor rotor LH.

NG

CLEAN OR REPLACE FRONT SPEED SENSOR LH OR COMPONENT WITH FRONT SPEED SENSOR ROTOR LH

OK

7.	CHECK VEHICLE SPECIFICATION

(a) Check the vehicle specification.

Result	Proceed to
w/o AVS	A
w/ AVS	B

B

GO TO STEP 10

A

8.	INSPECT HARNESS AND CONNECTOR (FRONT SPEED SENSOR LH - BRAKE ACTUATOR ASSEMBLY)

(a) Make sure that there is no looseness at the locking part and the connecting part of the connectors.

OK:

The connector is securely connected.

(b) Disconnect the A41 skid control ECU (brake actuator assembly) connector.

(c) Disconnect the A92 front speed sensor LH connector.

(d) Check both the connector case and the terminals for deformation and corrosion.

OK:

No deformation or corrosion.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
A92-3 (FL+) - A41-22 (FL+)	Always	Below 1 Ω
A92-3 (FL+) or A41-22 (FL+) - Body ground	Always	10 kΩ or higher
A92-4 (FL-) - A41-21 (FL-)	Always	Below 1 Ω
A92-4 (FL-) or A41-21 (FL-) - Body ground	Always	10 kΩ or higher

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

9.	INSPECT BRAKE ACTUATOR ASSEMBLY (SENSOR POWER SOURCE CIRCUIT)

(a) Reconnect the A41 skid control ECU (brake actuator assembly) connector.

*a Front view of wire harness connector (to Front Speed Sensor LH)

(b) Make sure that there is no looseness at the locking part and the connecting part of the connectors.

OK:

The connector is securely connected.

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

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

Standard Voltage:

Tester Connection	Condition	Specified Condition
A92-3 (FL+) - Body ground	Engine switch on (IG)	11 to 14 V

OK

REPLACE FRONT SPEED SENSOR LH

NG

REPLACE BRAKE ACTUATOR ASSEMBLY

10.	INSPECT FRONT SKID CONTROL SENSOR WIRE LH

(a) Make sure that there is no looseness at the locking part and the connecting part of the connectors. OK: The connector is securely connected.

*a Front view of front skid control sensor wire LH *b (to Sensor Side Connector) *c (to Vehicle Side Connector)

(b) Disconnect the z14 and A90 front skid control sensor wire LH connector.

(c) Check both the connector case and the terminals for deformation and corrosion.

OK:

No deformation or corrosion.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
z14-1 (FL+) - A90-3 (FL+)	Always	Below 1 Ω
z14-1 (FL+) or A90-3 (FL+) - Body ground and other terminals	Always	10 kΩ or higher
z14-2 (FL-) - A90-4 (FL-)	Always	Below 1 Ω
z14-2 (FL-) or A90-4 (FL-) - Body ground and other terminals	Always	10 kΩ or higher

NG

REPLACE FRONT SKID CONTROL SENSOR WIRE LH

OK

11.	CHECK HARNESS AND CONNECTOR (FRONT SKID CONTROL SENSOR WIRE LH - BRAKE ACTUATOR ASSEMBLY)

(a) Make sure that there is no looseness at the locking part and the connecting part of the connectors.

OK:

The connector is securely connected.

(b) Disconnect the A41 skid control ECU (brake actuator assembly) connector.

(c) Check both the connector case and the terminals for deformation and corrosion.

OK:

No deformation or corrosion.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
A90-3 (FL+) - A41-22 (FL+)	Always	Below 1 Ω
A90-3 (FL+) or A41-22 (FL+) - Body ground	Always	10 kΩ or higher
A90-4 (FL-) - A41-21 (FL-)	Always	Below 1 Ω
A90-4 (FL-) or A41-21 (FL-) - Body ground	Always	10 kΩ or higher

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

12.	INSPECT BRAKE ACTUATOR ASSEMBLY (SENSOR POWER SOURCE CIRCUIT)

(a) Reconnect the A41 skid control ECU (brake actuator assembly) connector.

*a Front view of front skid control sensor wire LH (to Front Speed Sensor LH)

(b) Reconnect the A90 front skid control sensor wire LH connector.

(c) Make sure that there is no looseness at the locking part and the connecting part of the connectors.

OK:

The connector is securely connected.

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

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

Standard Voltage:

Tester Connection	Condition	Specified Condition
z14-1 (FL+) - Body ground	Engine switch on (IG)	11 to 14 V

OK

REPLACE FRONT SPEED SENSOR LH

NG

REPLACE BRAKE ACTUATOR ASSEMBLY