C1175 — Speed Wheel Sensor LR Input Circuit Failure

C1175 — Speed Wheel Sensor LR Input Circuit Failure. A fault in the sensor and actuator circuits. The car is usually drivable while you plan the repair. Typical causes: open or shorted wiring in the circuit, blown fuse feeding the circuit, control module driver fault.

chassis (brakes/steering/suspension)

Is it safe to drive?

Short-term driving is OK In most cases the car remains drivable, possibly with reduced performance or a disabled auxiliary system. If symptoms include stalling, no-start or brake/steering warnings, treat it as urgent.

How to diagnose with an OBD scanner

Read the code and freeze frame Connect an OBD2 scanner, confirm C1175 is stored, and save the freeze frame data — it shows engine conditions when the fault was detected.
Check for companion codes and TSBs Related codes often reveal the real root cause. Also check manufacturer technical service bulletins (TSB) for your make and model — many C0xxx issues have factory fixes or software updates. Search by VIN on the manufacturer site or nhtsa.gov.
Inspect wiring and connectors Visually inspect the wiring harness and connectors related to the speed wheel sensor LR input circuit for damage, corrosion, chafing or poor contact.
Subsystem check Measure reference voltage, ground and signal continuity at the component connector.
Subsystem check Wiggle-test the harness while watching the signal in live data — dropouts reveal broken wires.
Verify the repair Clear the code, complete a full drive cycle including the conditions from the freeze frame, and confirm C1175 does not return.

Approximate repair cost

Repair cost depends on which component actually failed. Typical scenarios for C1175 (parts and labor, USD, independent shop rates): Repair wiring or connectors: $80–$250; Control module repair: $300–$1,000; Replace the faulty sensor or actuator: $150–$500. Overall, fixing C1175 usually costs between $80 and $1,000. An accurate diagnosis before buying parts saves money — the most expensive scenario is rarely the first one to check.

Common questions

What is the most common cause of C1175?

The most common causes are: open or shorted wiring in the circuit, blown fuse feeding the circuit, control module driver fault.

How do I diagnose C1175 myself?

Start with a scan: confirm C1175, save the freeze frame and note any companion codes. Then inspect the wiring and connectors related to the speed wheel sensor LR input circuit, and verify the suspect component against live data before buying parts.

How much does it cost to fix C1175?

Repair wiring or connectors — $80–$250; Control module repair — $300–$1,000; Replace the faulty sensor or actuator — $150–$500. Exact cost depends on the root cause, your vehicle and local labor rates — a proper diagnosis is the cheapest first step.

Is it safe to drive with C1175?

In most cases the car remains drivable, possibly with reduced performance or a disabled auxiliary system. If symptoms include stalling, no-start or brake/steering warnings, treat it as urgent.

Will C1175 clear itself?

Sometimes C1175 clears after a few drive cycles if the fault was intermittent — for example a loose connector or a tank of bad fuel. The underlying cause usually remains, so the code tends to return. Clear it once; if it comes back, diagnose rather than erase it repeatedly.

DTC C1175 points to a problem with the left-rear wheel speed sensor input circuit — one of the components your vehicle relies on to monitor rotational speed at each corner. This data feeds multiple safety systems, including anti-lock braking and stability control. When the Powertrain Control Module (PCM) or ABS controller detects that the signal from this sensor has gone missing, fallen outside acceptable parameters, or表现得 erratic, it logs C1175 and triggers a warning lamp on the dashboard.

Think of the wheel speed sensor as a small electromagnetic device bolted near the wheel hub. As a toothed reluctor ring spins with the wheel, the sensor generates an AC voltage pulse — each pulse represents one tooth passing by. The controller counts these pulses to calculate rotational speed. Under normal operation, the PCM expects a clean, steady signal that matches the vehicle's calculated speed based on gear ratio and tire diameter. When the controller sees something wrong with this signal — whether it's absent, intermittent, or out of range — it flags the fault. The diagnostic system requires the abnormality to persist for a set number of drive cycles before lighting up the check engine or ABS warning light, which is why the issue might come and go before the light appears.

Symptoms of C1175

The ABS or stability control warning lamp illuminates on the instrument cluster
The anti-lock system may not activate during an emergency stop, or traction control becomes unresponsive
The speedometer may display inaccurate readings or fluctuate unexpectedly
Some vehicles enter a reduced-power or "limp home" mode to protect drivetrain components
The affected system operates inconsistently or fails to function at all
Fuel consumption climbs in certain applications because the PCM cannot accurately calculate vehicle speed
In rare cases, the engine stalls or fails to start if the module interprets the sensor failure as a safety risk

Common Causes of C1175

Corrosion, looseness, or physical damage at the wheel speed sensor connector — the most frequent source of this code
Broken, chafed, or disconnected wiring in the sensor circuit, often caused by age, heat cycles, or road debris
A blown fuse protecting the sensor circuit, which cuts power and kills the signal entirely
Insufficient or interrupted ground at the sensor body or the control module itself
Failure of the wheel speed sensor itself due to wear, contamination, or mechanical damage
An internal fault within the ABS or PCM driver circuit that controls the sensor input
Water intrusion into the connector, common on vehicles frequently exposed to rain, snow, or car washes

How to Diagnose C1175

Hook up a compatible OBD2 scanner, retrieve code C1175, and record the associated freeze frame data — this snapshot shows engine speed, load, temperature, and vehicle speed at the exact moment the fault was detected and is the most reliable starting point.
Look for any related diagnostic trouble codes stored alongside C1175; secondary codes often point directly to the root cause, such as a power supply issue or a communication fault between modules.
Check manufacturer technical service bulletins using your vehicle identification number on the automaker's website or nhtsa.gov — many C1175 occurrences have documented factory fixes, including software updates or known connector positions that require rerouting.
Perform a thorough visual inspection of the wiring harness and the left-rear wheel speed sensor connector for cracked insulation, greenish corrosion buildup, bent pins, or any sign that the connector has been pulled loose.
With the connector disconnected, use a digital multimeter to verify that reference voltage, ground continuity, and signal circuit resistance all fall within the specifications listed in your service manual.
Clear the code, drive the vehicle through a complete drive cycle that reproduces the conditions stored in the freeze frame, then rescan to confirm whether C1175 reappears — a recurring code confirms an active fault rather than a temporary electrical glitch.

Repair Options and Costs

The repair strategy for C1175 should follow a logical sequence, starting with the least expensive and most common fixes before moving to component replacement:

Wiring repair or connector replacement: $80–$250 — cleaning corroded pins, sealing a leaking connector, or soldering a broken wire inside the harness typically resolves the majority of C1175 complaints.
Sensor replacement: $150–$500 — if testing confirms the sensor itself has failed electrically or is physically damaged beyond repair, installing a new unit is the standard solution.
Control module diagnosis or repair: $300–$1,000 — in rare situations where the PCM or ABS controller internal driver has failed, professional module-level repair or replacement becomes necessary.

Overall, fixing C1175 typically runs between $80 and $1,000 depending on which part of the circuit is at fault. A methodical diagnosis before purchasing parts always saves money — the most expensive repair scenario is rarely where you should start, and most failures trace back to a simple wiring or connector issue rather than a failed control module.

Can You Drive with C1175?

In most cases the vehicle remains drivable when C1175 is stored, though you may notice reduced system performance, an active warning lamp, or limited traction and stability control functions. If the car exhibits stalling, failure to start, or warnings related to braking or steering, treat the condition as urgent and have it inspected immediately. Otherwise, schedule service at your earliest convenience — prolonged driving without functional anti-lock or stability systems increases stopping distance and reduces recovery ability in adverse conditions.