BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: ELECTRONICALLY CONTROLLED BRAKE SYSTEM (for Gasoline Model with Electric Parking Brake System): C050C12; Left Rear Wheel Speed Sensor Circuit Short to Battery; 2023 MY Corolla Corolla Hatchback GR Corolla [11/2022

Last Modified: 07-31-2024	6.11:8.1.0	Doc ID: RM1000000028D6O
Model Year Start: 2023	Model: GR Corolla	Prod Date Range: [11/2022 - 08/2023]
Title: BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: ELECTRONICALLY CONTROLLED BRAKE SYSTEM (for Gasoline Model with Electric Parking Brake System): C050C12; Left Rear Wheel Speed Sensor Circuit Short to Battery; 2023 MY Corolla Corolla Hatchback GR Corolla [11/2022 - 08/2023]

DTC

C050C12

Left Rear Wheel Speed Sensor Circuit Short to Battery

DESCRIPTION

Each speed sensor detects wheel speed and sends signals to the skid control ECU (brake actuator assembly). These signals are used by the ABS control.

The speed sensor detects the magnetic fields of the speed sensor rotor as it rotates and outputs a pulse signal.

The frequency of the pulse varies in accordance with the rotational speed of the speed sensor rotor and the system uses this to determine the wheel speed.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area
C050C12	Left Rear Wheel Speed Sensor Circuit Short to Battery	A short to +B in the speed sensor signal circuit is detected for 0.12 seconds or more.	Rear speed sensor LH (rear axle hub and bearing assembly LH) Wire harness or connector Skid control sensor wire LH (No. 2 parking brake wire assembly) Skid control ECU (brake actuator assembly)

WIRING DIAGRAM

PROCEDURE

1.	CHECK HARNESS AND CONNECTOR (SENSOR GROUND CIRCUIT)

(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 skid control sensor wire LH (No. 2 parking brake wire assembly) (to Rear Speed Sensor LH (Rear Axle Hub and Bearing Assembly LH))

(b) Disconnect the n2 rear speed sensor LH (rear axle hub and bearing assembly LH) connector.

OK:

No deformation or corrosion.

(d) Turn the ignition switch to ON.

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

Standard Voltage:

Tester Connection	Condition	Specified Condition
n2-2 (RL+) - n2-1 (RL-)	Ignition switch ON	11 to 14 V

REPLACE REAR AXLE HUB AND BEARING ASSEMBLY LH

for Double Wishbone Type Suspension: Click here

for Torsion Beam Type Suspension: Click here

2.	CHECK HARNESS AND CONNECTOR (SENSOR GROUND CIRCUIT)

(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 wire harness connector (to Skid Control Sensor Wire LH (No. 2 Parking Brake Wire Assembly))

(b) Disconnect the nO2 skid control sensor wire LH (No. 2 parking brake wire assembly) connector.

OK:

No deformation or corrosion.

(d) Turn the ignition switch to ON.

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

Standard Voltage:

Tester Connection	Condition	Specified Condition
nO2-1 (RL+) - nO2-2 (RL-)	Ignition switch ON	11 to 14 V

REPLACE NO. 2 PARKING BRAKE WIRE ASSEMBLY

3.	CHECK HARNESS AND CONNECTOR (NO. 2 PARKING BRAKE WIRE ASSEMBLY - 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.

*a	Front view of wire harness connector (to Skid Control Sensor Wire LH (No. 2 Parking Brake Wire Assembly))

(b) Disconnect the A51 skid control ECU (brake actuator assembly) connector.

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

OK:

No deformation or corrosion.

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

Standard Voltage:

Tester Connection	Condition	Specified Condition
nO2-2 (RL-) - Body ground	Always	Below 1.5 V

REPAIR OR REPLACE HARNESS OR CONNECTOR

4.	CHECK HARNESS AND CONNECTOR (NO. 2 PARKING BRAKE WIRE ASSEMBLY - 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 A51 skid control ECU (brake actuator assembly) 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
nO2-1 (RL+) or A51-39 (RL+) - nO2-2 (RL-) or A51-23 (RL-)	Always	10 kΩ or higher

REPLACE BRAKE ACTUATOR ASSEMBLY

REPAIR OR REPLACE HARNESS OR CONNECTOR