Left Front Wheel Speed Sensor Input Signal Missing
Table of contents
C1233 MAZDA Possible Causes
- Faulty Left Front Wheel Speed Sensor
- Left Front Wheel Speed Sensor harness is open or shorted
- Left Front Wheel Speed Sensor circuit poor electrical connection
How do I fix code C1233 MAZDA?
Check the “Possible Causes” listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector’s pins.
Tech Notes
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Cost of diagnosing the C1233 MAZDA code
The cost of diagnosing the C1233 MAZDA code is 1.0 hour of labor. The auto repair labor rates vary by location, your vehicle’s make and model, and even your engine type. Most auto repairs shops charge between $75 and $150 per hour.
Possible Symptoms
- Anti-Lock Brake System (ABS) Warning Light ON
- Engine Light ON (or Service Engine Soon Warning Light)
C1233 MAZDA Description
The Anti-Lock Brake System (ABS) Module receives wheel speed readings from each wheel speed sensor and processes this information to determine if an ABS event is necessary. The wheel speed sensor detects the magnetic field of the sensor ring as it passes the face of the active wheel speed sensor.
The active wheel speed sensor generates a signal that is sent to the ABS module. The wheel speed sensor circuitry connects to the ABS module through 2 wires and a connector at each wheel speed sensor. When the ignition is turned to the RUN position, the ABS module carries out a self-test by sending a reference voltage to all of the wheel speed sensors through their circuitry to determine if they are functional.
The ABS module continuously monitors and compares the rotational speed of each wheel and when it detects an impending wheel lock, modulates the brake pressure to the appropriate brake caliper. This is accomplished by triggering the hydraulic control unit (HCU) to open and close the appropriate solenoid valves. Once the affected wheel returns to normal speed, the ABS module returns the solenoid valves to their normal position and normal (base) braking resumes.