P0573 — Cruise Control/Brake Switch A Circuit High

P0573 — Cruise Control/Brake Switch A Circuit High. A fault in the ABS / stability control. Short, gentle driving to a shop is usually possible. Typical causes: faulty ABS module or pump motor, damaged tone (reluctor) ring on the hub, blown fuse or low voltage to the ABS module.

powertrain (engine/transmission)

Is it safe to drive?

Avoid using cruise until P0573 is repaired The vehicle can usually be driven with P0573, but cruise control may be unavailable or release unexpectedly. Confirm that the brake lamps and brake pedal operation are normal, and avoid using cruise until the circuit has been diagnosed and repaired.

Typical symptoms

  • P0573 remains stored in the OBD2 memory.
  • Cruise control will not engage or may disengenge unexpectedly.
  • The brake switch reading may remain high regardless of pedal position.
  • A brake, ABS, or cruise-related warning message may appear.
  • Brake lamps may remain illuminated or fail to illuminate when the pedal is pressed.
  • The condition may occur intermittently as the pedal or vehicle is exposed to vibration.

Common causes

  • A failed or misadjusted brake pedal position switch can leave the P0573 brake-switch input at an unintended high voltage.
  • A short to battery voltage in brake switch circuit A can cause the controller to record P0573.
  • Corrosion, a loose terminal, or high resistance in the brake switch connector can create an intermittent high reading.
  • Damaged wiring, a poor ground, or an impaired voltage-reference circuit can falsely trigger P0573.
  • An internal fault in the ABS, cruise control, or powertrain control module can misread the brake switch signal.

How to diagnose with an OBD scanner

  1. Confirm P0573 with an OBD2 scan Connect an ELM327 adapter and use AIScanAuto or another OBD2 scanner to read stored codes and freeze-frame data. Confirm that P0573 is active, note any freeze-frame conditions, and determine whether the brake-switch state changes when the pedal is pressed and released.
  2. Inspect the brake switch and connector Locate the brake pedal position switch and examine its connector, terminals, and mounting position. Look for corrosion, water intrusion, a loose plug, a bent pin, or a switch that does not move fully when the pedal is released.
  3. Test circuit A voltage Using the service wiring diagram, back-probe the brake switch circuit at the switch and control-module connector. Verify that the voltage changes as expected between pedal positions and that circuit A is not being held above the controller's permitted threshold.
  4. Check wiring, grounds, and module inputs Perform a pull test on the relevant harness sections and inspect splices near the brake pedal. Confirm that high P0573 readings are not caused by a poor ground, damaged insulation, or a short to battery voltage before condemning the controller.
  5. Repair and verification Replace the defective brake switch, repair the connector or wiring, and correct any pedal-switch adjustment. Clear P0573 with the scanner, operate the pedal through its full range, and road-test to confirm that cruise engages and releases normally.

Approximate repair cost

A typical independent-shop estimate for diagnosing and repairing P0573 is $120-$400, depending on whether the brake switch, connector, wiring, or control-module input requires service. This range is an estimate and varies by region, labor rate, and parts availability.

Common questions

What does P0573 mean on this vehicle?

P0573 means the controller is detecting an abnormally high voltage on brake switch circuit A, commonly caused by a defective switch, connector fault, or shorted wiring.

Can I continue driving with P0573 stored?

You can generally drive, but do not rely on cruise control until P0573 is repaired. If the brake lamps, pedal operation, or ABS warning lights are abnormal, stop and have the vehicle inspected.

Does P0573 require replacement of the cruise control module?

Usually not. Most P0573 faults begin with the brake switch, its connector, or circuit A; the ABS or cruise controller should be tested only after those items check out.

Why might P0573 return after the brake switch is replaced?

P0573 can return if the replacement switch is misadjusted, a connector remains corroded, wiring still contains a short to voltage, or the control-module input is damaged.

When your check engine light comes on and a shop scanner displays P0573, the engine control module is telling you it has spotted an abnormal voltage condition in the cruise control and brake switch circuit. P0573 falls into the powertrain category of OBD2 codes, which means it involves systems that directly affect engine operation or transmission function. Specifically, this fault indicates that the voltage on the switch A circuit for cruise control and braking has climbed higher than the acceptable range—typically approaching full battery voltage. That reading tells the computer something is pulling the signal line up when it should be low or switching normally, which points to a short to power, an open ground path, or a defective switch itself.

To set P0573, the control module monitors the cruise control/brake switch circuit over multiple drive cycles and compares the live voltage against its programmed thresholds. When readings stay out of range long enough to trigger a confirmed fault, the code sets and a freeze frame snapshot is captured. That snapshot records engine RPM, load percentage, coolant temperature, and vehicle speed at the exact moment the problem occurred. Technicians use that data to recreate the failure condition during testing, which makes diagnosis faster and more accurate.

Symptoms of P0573

P0573 affects the interaction between your braking system and cruise control, so you may notice one or more of the following:

  • ABS warning light illuminated on the dashboard
  • Stability control system disabled or showing a fault message
  • Brake pedal feeling different than normal, sometimes with subtle pulsation
  • ABS failing to activate during hard braking, even though base brakes still function
  • Cruise control refusing to engage or shutting off unexpectedly
  • Speedometer reading inconsistently or appearing to malfunction

Common Causes

The underlying issues that trigger P0573 vary in complexity. The most frequent culprits include:

  • Open or disconnected ground wire at the cruise control/brake switch
  • Signal wire shorted directly to battery positive voltage
  • Defective cruise control/brake switch pulling the circuit high
  • Damaged wiring harness or corroded connector at the ABS sensor
  • Failed wheel speed sensor providing incorrect data to the ABS module
  • Faulty ABS control module or pump motor assembly
  • Damaged tone ring (reluctor) on the wheel hub covered in metal debris
  • Blown fuse or insufficient voltage supply reaching the ABS module

How to Diagnose P0573

Follow these steps to identify the root cause before replacing any parts:

  1. Connect an OBD2 scanner and verify that P0573 is present in the stored codes. Record the freeze frame data—this snapshot reveals what the engine was doing when the fault first appeared.
  2. Scan for any additional diagnostic trouble codes. Related codes often point to the underlying problem, whether in the wheel speed sensors, the ABS module, or the brake switch circuit itself.
  3. Pull up manufacturer technical service bulletins (TSB) for your specific make and model using your VIN. Some P0573 cases have documented factory fixes or require a software update from the dealer.
  4. Perform a visual inspection of all wiring and connectors associated with the cruise control switch and ABS sensors. Look for chafed insulation, corrosion, broken pins, or loose connections.
  5. With the cruise control/brake switch disconnected, probe the signal wire at the harness side. If voltage remains high with the component unplugged, the harness itself has a short to power. If the voltage drops to normal ground levels, the switch is faulty.
  6. Monitor live wheel speed sensor data on the scanner while driving slowly. A faulty sensor will drop out, freeze at zero, or display implausible readings compared to the other three wheels.
  7. Clear P0573, complete a drive cycle that reproduces the conditions stored in the freeze frame, and verify the code does not return.

Repair Options and Costs

Once you have identified the failing component, here are the typical repair costs:

  • ABS module repair or replacement: $400–$1,200
  • Wheel speed sensor replacement: $120–$350
  • Sensor wiring repair: $80–$250

The total cost to fix P0573 typically ranges from $80 to $1,200 depending on what actually failed. Diagnose before you buy—replacing an expensive ABS module when the real issue is a $15 sensor wire or a corroded connector wastes money and time.

Can You Drive with P0573?

Your base braking system will continue to work, so you can drive the vehicle with caution. However, P0573 disables the ABS and electronic stability control, which means your stopping distances increase significantly on wet, icy, or uneven surfaces. Do not delay the repair. Get the code diagnosed and fixed before relying on the vehicle in challenging driving conditions.