C0045 - LEFT REAR WHEEL SPEED SENSOR CIRCUIT MALFUNCTION

Description of DTC code C0045

The Electrical Brake Control Module (EBCM) is responsible for providing an ignition signal to the Wheel Speed Sensors. The sensors then tell the module, via a square wave signal, what the wheel speed is. To achieve this, these sensors have a reluctor ring, which with each movement it makes creates interruptions in the magnetic field, in order to give pulses that are sent to the EBCM or other module that requires it, to determine how fast the wheel rotates.

The setting of diagnostic code C0045 OBD2 occurs when one of the wheel speed sensors malfunctions. In this case, the code specifically states that it is on the sensor for the left rear wheel.

How does the C0045 Generic Fault Code work?

In the Fault Code Library, this is part of the Chassis Codes. This code is notable for diagnosing the Vehicle's Speed Sensor (VSS). The Speed Sensor gets an electrical signal from the Electronic Brake Control Module, as the wheel rotates this module uses the frequency of the sensor signal to calculate the vehicle speed.

Vehicles with electronic brake control systems have speed sensors on all 4 wheels, this is called a four-channel ABS Brake System. The speed sensors are magnetic sensors located in the transaxle, where the odometer cable was installed. Consequently, this leads to the system detecting the vehicle fault code C0045.

Symptoms of fault code C0045

Check Engine light illuminated.
ABS warning light
Inconsistencies concerning vehicle speed are displayed on the dash.
Knocking from brake switch.

Causes of OBD2 C0045

DTC C0045 OBDII code setting is due to one or more of the following factors:

The Left Rear Wheel Speed Sensor circuit wiring may have deficiencies causing a short.
The Left Rear Wheel Speed Sensor connector may have high levels of corrosion.
Possibly the Left Rear Wheel Speed Sensor is in poor condition.

Possible solutions of the DTC code C0045

For the respective solution of the C0045 OBD2 fault code you should take into account the following:

Consult the TSBs provided by the manufacturer.
Inspect all the wires and other components of the left rear wheel speed sensor Verify that they are not burned, corroded, or worn, which causes the malfunction. Repair as necessary.
Perform voltage tests on the Left Rear Wheel Speed Sensor The readings you obtain should match the values specified by the manufacturer. If not, corrections should be made.
Using the manufacturer's diagnostic steps, verify that the Left Rear Wheel Speed Sensor is not defective. If you discover damage causing the malfunction, make adjustments as applicable, including replacing the sensor if necessary.