Left Front Wheel Speed Sensor Circuit High Voltage
The C1190 code indicates that the ABS or stability control module has detected an abnormally high voltage on the left front wheel speed sensor input circuit, consistent with a short to battery positive (B+). This occurs when the sensor signal voltage exceeds the expected threshold, preventing reliable wheel speed readings. The condition is typically caused by damaged wiring insulation, a faulty connector, or an internal sensor failure that allows battery voltage to contaminate the signal circuit. As a result, active safety systems such as ABS, traction control (TCS), and electronic stability control (ESP) may become disabled or intervene incorrectly during maneuvers involving the left front wheel.
1. Commonly Affected Makes
2. Most Common Causes
- Short circuit between the left front sensor signal wire and a B+ power wire in the harness
- Left front wheel speed sensor with internal damage causing current leakage to the output circuit
- Sensor or ABS module connector with bent, corroded, or moisture-bridged pins between signal and power terminals
- Mechanical damage to the harness (chafing, melting) exposing conductors and contacting positive wires
- Internal failure of the ABS/ESP control module incorrectly applying battery voltage to the input circuit
3. Symptoms You Will Notice
- ABS warning light illuminated
- Traction control or stability control warning lights on
- ABS, traction control, or stability control systems disabled or functioning erratically
- Possible loss of power assist or unusual brake pedal feel during low-traction conditions
4. Step-by-Step Diagnosis
Scan the ABS module for C1190 and any related codes
Visually inspect the left front wheel speed sensor wiring and connector for damage, corrosion, or shorts
Measure voltage at the sensor connector with the ignition on; compare to manufacturer specifications
Check for continuity between the sensor signal circuit and B+ to confirm a short
Test the sensor resistance and output signal while spinning the wheel
If wiring and sensor are good, suspect a faulty ABS module
5. Frequently Asked Questions
Is it safe to drive?▼
Driving is not recommended because the ABS, traction control, and stability control systems may be disabled or operate incorrectly, increasing the risk of loss of control during emergency maneuvers or on slippery surfaces.
How much does it cost to fix?▼
Repair costs typically range from $150 to $600, depending on whether the issue is a simple wiring repair, a sensor replacement ($50–$200), or an ABS module replacement ($300–$800).