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Severity: High Code type: Manufacturer-specific (Chevrolet)

Chevrolet C0545 Code: Steering Wheel Torque Sensor

The electric power steering module can't trust its torque sensor, so steering assist may cut out.

At a glance

Severity: 4/5 – High4/5

Severity: High

Meaning
Steering Wheel Torque Sensor
System
Brakes, ABS & Chassis · Chassis
Safe to drive?
With caution
Typical repair cost
$0–$1,600
DIY difficulty
Hard

On Chevrolets with column-mounted electric power steering, such as the Cobalt, HHR, Malibu and Equinox, a torque sensor on the steering shaft tells the power steering control module (PSCM) how hard and in which direction you're turning the wheel. It's a 5-volt sensor with two signals that sit near 2.5 V when the wheel is at rest and move in opposite directions as you steer. C0545 sets when either signal goes outside its valid window (roughly below 0.25 V or above 4.75 V) or the two stop agreeing; a variant with the symptom byte 4B means the sensor calibration hasn't been learned, typically after the column or PSCM was replaced. When the PSCM sees this fault it stops assisting, so the steering suddenly becomes heavy and the driver information center shows a power steering warning.

How to read C0545

How to read C0545C10253454
  1. C Chassis
  2. 0 Generic (SAE)
  3. 5 Brakes, ABS & Chassis
  4. 45 Specific fault

Symptoms

  • Steering suddenly becomes heavy, especially at parking-lot speeds
  • POWER STEERING or SERVICE POWER STEERING message on the dash
  • Assist comes back after switching the car off and on, then drops out again
  • Steering feels uneven, heavier turning one way than the other
  • StabiliTrak or traction control warning on some models
  • Problem appears on bumps or when the wheel is turned to full lock

Possible causes

Ranked by how often each cause is behind this code (editorial estimate).

  1. Loose or corroded torque sensor connector at the steering column under the dash 30%
  2. Failed torque sensor inside the steering column (serviced as part of the column assembly) 28%
  3. Calibration not learned after a column or PSCM replacement (symptom byte 4B) 14%
  4. Weak battery or low system voltage causing the PSCM to drop assist and log sensor faults 12%
  5. Damaged wiring between the sensor and the PSCM (pinched by column adjustment or previous dash work) 10%
  6. Internal PSCM failure 6%

Diagnosis step by step

Diagnostic flow: C05451Read the PSCM codes and symptom byte2Rule out low voltage3Watch both torque signals in livedata4Check the sensor connector andcircuits5Wiggle test while monitoring6Replace, then calibrate
  1. Read the PSCM codes and symptom byte

    Use a scan tool that can talk to the power steering control module. Write down C0545 with its symptom byte and any voltage codes; 4B points to a missing calibration, while 00 points to the signal circuits or the sensor.

    Tools: OBD-II scanner

  2. Rule out low voltage

    Load-test the battery and check charging voltage, which should be roughly 13.5 to 14.8 V with the engine running and the steering being turned. The EPS motor draws heavy current when parking, and a weak battery or poor ground can cause assist dropouts that look like a sensor failure.

    Tools: Multimeter

  3. Watch both torque signals in live data

    With the engine running and the wheel released, both torque sensor signals should read close to 2.5 V. Turning right should move one signal up and the other down by a similar amount, and turning left does the opposite; a signal that jumps, sticks or doesn't mirror the other shows the fault.

    Tools: OBD-II scanner

  4. Check the sensor connector and circuits

    Remove the lower column cover and inspect the torque sensor connector for loose terminals and corrosion. With the key on, the 5-volt reference should read about 4.8 to 5.2 V and the low reference should show under 2 ohms to ground with the key off.

    Tools: Multimeter, Screwdriver, Flashlight

  5. Wiggle test while monitoring

    Watch the two signals while gently flexing the harness near the column and adjusting the tilt. A dropout during the wiggle means a wiring or terminal problem that can be repaired without buying a column.

    Tools: OBD-II scanner

  6. Replace, then calibrate

    If the signals are wrong with good wiring, the torque sensor is bad; on these cars it comes with the column assembly. After replacing the column or the PSCM, the torque sensor and steering position calibrations must be run with a scan tool, or the assist won't work correctly.

    Tools: OBD-II scanner, Torque wrench

Where the parts are

Charging system and control modules – C05451234567
Charging system and control modules
  1. 1Battery
  2. 2Alternator
  3. 3Engine computer (ECM)
  4. 4CAN bus
  5. 5Transmission
  6. 6Wheel speed sensor
  7. 7High-voltage battery

Repair options & costs

RepairDIY?Estimated cost
Clean and reseat torque sensor connector Yes $0–$150
Torque sensor calibration only (scan tool) No $80–$200
Repair sensor wiring at the column No $100–$300
Replace PSCM with programming and calibration No $400–$950
Replace steering column assembly with calibration No $700–$1,600

Rough US estimates for parts and labor; shop rates vary by region. Not a quote.

Emissions / smog test impact

Depends

C0545 doesn't turn on the check engine light, so it has no effect on an OBD emissions test. In states with a safety inspection, a steering system warning or noticeably heavy steering can lead to a failure.

Frequently asked questions

Is the torque sensor the same as the steering angle sensor?

No. The torque sensor measures how hard you're twisting the wheel so the motor knows how much to help, while the angle (position) sensor tells the stability system where the wheel is pointed. C0545 is about torque, and losing it switches off power assist.

Why does restarting the car bring the power steering back?

The PSCM rechecks the sensor at every start. If the fault is intermittent, like a loose terminal, the signals pass the check and assist returns until the next dropout. That pattern points strongly toward a connection problem.

Was there a recall for loss of power steering on these cars?

Certain model years of the Cobalt, HHR, Malibu and related GM cars were recalled for sudden loss of electric power steering assist. Check your VIN on the NHTSA recall site or with a Chevrolet dealer before paying for a column.

Can I replace just the torque sensor?

On most of these Chevrolets the torque sensor isn't sold separately; it's part of the steering column assembly with the motor. A used column is possible, but it still needs the calibration procedure afterward.

Why did C0545 appear after my column was replaced?

A new or used column has to be calibrated to the PSCM. Until that's done, the module sets C0545 with symptom byte 4B and may give weak or uneven assist.

Sources