DTC C0506-23: Right Front Wheel Speed Sensor Signal Stuck Low [12/2019 - ]: Procedure

1. Check the front speed sensor RH installation.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   *1	Front Speed Sensor RH
   *a	Correct
   *b	Incorrect
   *c	8.5 N.m (87 kgf/cm, 75 in.lbf)
   *d	No clearance

   OK

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

   The installation bolt is tightened properly.

   Torque 

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

   Result

   Proceed to
   OK
   NG

Result: 

NG 

REINSTALL OR REPLACE FRONT SPEED SENSOR RH. Refer to  REMOVAL [12/2019 - 10/2022]  , or refer to  REMOVAL [10/2022 - ] 

Result: 

OK 

See step  2

1. Remove the front speed sensor RH.

   Refer to REMOVAL [12/2019 - 10/2022] , or refer to REMOVAL [10/2022 - ]

2. Check the front speed sensor tip RH.

   OK

   The front speed sensor tip RH is free of scratches, oil, and foreign matter.

   NOTE:

   • If there is oil or foreign matter on the front speed sensor RH, clean the front speed sensor RH.
   • If the front speed sensor RH is damaged, replace the front speed sensor RH with a new one.

   Result

   Proceed to
   OK
   NG

Result: 

NG 

CLEAN OR REPLACE FRONT SPEED SENSOR RH 

Result: 

OK 

See step  3

1. Start the engine.
2. Perform a road test.
3. Check the front speed sensor RH output value.

   Chassis > Brake/EPB > Data List 

   Tester Display	Measurement Item	Range	Normal Condition	Diagnostic Note
   FR Wheel Speed	Front wheel speed sensor RH 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
   FR Wheel Speed

   OK

   The output value changes in accordance with the vehicle speed.

   Result

   Proceed to
   OK
   NG

Result: 

OK 

USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [12/2019 - ] 

Result: 

NG 

See step  4

1. Turn the ignition switch off.
2. Make sure that there is no looseness at the locking part and the connecting part of the connectors.

   OK

   The connector is securely connected.

3. Disconnect the A39 skid control ECU (brake actuator assembly) connector.
4. Disconnect the A40 front speed sensor RH connector.
5. Check both the connector case and the terminals for deformation and corrosion.

   OK

   No deformation or corrosion.

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

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   A40-1 (FR+) - A39-7 (FR+)	Always	Below 1 Ω
   A40-1 (FR+) or A39-7 (FR+) - Body ground	Always	10 kΩ or higher
   A40-2 (FR-) - A39-6 (FR-)	Always	Below 1 Ω
   A40-2 (FR-) or A39-6 (FR-) - Body ground	Always	10 kΩ or higher

   Result

   Proceed to
   OK
   NG

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR 

Result: 

OK 

See step  5

1. Remove the component with the front speed sensor rotor RH.

   Refer to REMOVAL [12/2019 - 10/2022] , or refer to REMOVAL [10/2022 - 11/2023] , or refer to REMOVAL [11/2023 - ]

2. Check the front speed sensor rotor RH.

   OK

   The front speed sensor rotor RH is free of scratches, oil, and foreign matter.

   NOTE:

   • If there is oil or foreign matter on the front speed sensor rotor RH, clean the front speed sensor rotor RH.
   • Do not use parts cleaner when cleaning the front speed sensor rotor RH.
   • If the front speed sensor rotor RH is damaged, replace the front speed sensor rotor RH with a new one.

   HINT: 

   • The front speed sensor rotor RH is incorporated into the front axle hub sub-assembly RH.
   • If the front speed sensor rotor RH needs to be replaced, replace it together with the front axle hub sub-assembly RH.

   Result

   Result	Proceed to
   OK	A
   NG (The front speed sensor rotor RH is damaged.)	B
   NG (There is foreign matter on the front speed sensor rotor RH.)	C

Result: 

A 

REPLACE FRONT SPEED SENSOR RH. Refer to  REMOVAL [12/2019 - 10/2022]  , or refer to  REMOVAL [10/2022 - ] 

Result: 

B 

REPLACE FRONT AXLE HUB SUB-ASSEMBLY RH. Refer to  REMOVAL [12/2019 - 10/2022]  , or refer to  REMOVAL [10/2022 - 11/2023]  , or refer to  REMOVAL [11/2023 - ] 

Result: 

C 

CLEAN FRONT SPEED SENSOR ROTOR RH