C1145: Right Front Wheel Speed Sensor Circuit Malfunction
The ABS module has detected a fault in the right front wheel speed sensor circuit. This indicates an erratic, missing, short-to-ground, short-to-voltage, or open circuit condition in the sensor or its wiring, preventing proper wheel speed monitoring for ABS, traction control (TCS), and stability control (ESC) systems.
1. Commonly Affected Makes
2. Most Common Causes
- Faulty right front wheel speed sensor (open or shorted coil)
- Damaged, corroded, or loose sensor wiring or connector
- Damaged, dirty, or missing teeth on the tone ring (reluctor)
- Incorrect air gap between sensor and tone ring
- Faulty ABS hydraulic control unit (HCU) or electronic brake control module (EBCM)
3. Symptoms You Will Notice
- ABS warning light illuminated
- Traction control or stability control warning lights on
- ABS system may not function during braking
- Possible loss of traction or stability control features
4. Step-by-Step Diagnosis
Scan for additional ABS codes and freeze frame data
Visually inspect the right front wheel speed sensor, wiring, and connector for damage, corrosion, or loose connections
Measure sensor resistance and compare to specifications (typically 1-2 kΩ)
Check for AC voltage output while spinning the wheel (should produce a small AC signal)
Inspect the tone ring for damage, debris, or missing teeth
Verify proper air gap between sensor and tone ring (usually 0.5-1.5 mm)
If all else is good, test the EBCM by swapping with a known good module or performing a module self-test
5. Frequently Asked Questions
Is it safe to drive?▼
You can still drive, but the ABS, traction control, and stability control systems will be disabled. Braking without ABS may cause wheel lockup in emergency situations. It is recommended to have the issue diagnosed and repaired promptly.
How much does it cost to fix?▼
Depending on the cause, repair costs typically range from $100 to $400 for a sensor replacement, up to $800 or more if the EBCM needs replacement.