Apex Automotive & Emissions
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OBD-II Diagnostic Trouble Code

C0045Left Rear Wheel Speed Sensor Circuit

High Severity

At a Glance

What It Means

The left rear wheel speed sensor circuit has a fault.

System

Brakes — ABS

Can I Drive?

Not recommended — risk of further damage.

Severity

High

Symptoms

  • ABS warning light illuminated
  • Traction/stability control lights on
  • ABS inoperative
  • Possible false activation

Common Causes

01Faulty wheel speed sensor
02Damaged tone ring
03Wiring damage from road debris
04Corrosion at connector
05Wheel bearing wear

How We Diagnose C0045

01

Scan & Verify

Confirm C0045 and check for related codes that may share a root cause.

02

Live Data Review

Pull real-time sensor data to isolate whether the fault is electrical, mechanical, or software-related.

03

Component Test

Perform targeted tests on the specific circuit or component flagged by the code.

04

Root Cause Repair

Repair or replace only what is confirmed faulty — no parts-swapping guesswork.

05

Verify & Clear

Clear the code, perform a drive cycle, and confirm the monitor passes before returning the vehicle.

Related Services

Frequently Asked

Will code C0045 clear itself?

OBD-II codes do not clear themselves. The underlying fault must be repaired and the monitor must pass during a drive cycle before the light extinguishes.

Can I pass an Arizona emissions test with C0045 active?

No. Any active check engine light is an automatic emissions test failure in Arizona. The code must be resolved and the relevant monitor must complete before testing.

How long does a diagnostic take?

Most diagnostic appointments at Apex take 45–90 minutes. Complex electrical faults may require additional time for circuit testing.