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Home / Codes / P0573
DTC code page

P0573: Brake Switch A Circuit High

Quick answer: The PCM sees the brake-switch A signal higher than the expected range or stuck in the applied direction.

Drivers also search this fault as brake switch a circuit high, brake pedal switch high input, P0573 brake switch high.

Severity: medium Family: powertrain Related paths: 6
Meaning

What P0573 usually means

P0573 is the high-input side of a very common brake-switch problem. In plain language, the PCM thinks the brake-switch A circuit is being held too high or behaving like the pedal is applied when it should not be. On many vehicles that is enough to shut cruise control down immediately and to confuse torque-management logic. The code does not always mean the switch itself is internally shorted high. A wiring issue, wrong adjustment, or feed-path problem can all make the brake signal look permanently applied or electrically implausible.

Fast triage

Start here before chasing parts

  • Scan first: save freeze-frame and pending codes before clearing anything.
  • Confirm the complaint: compare the stored code with current drivability symptoms.
  • Use context: trims, live data, and related codes usually narrow the fault faster than guesswork.
  • Work simplest to hardest: leaks, connectors, maintenance items, and known patterns before expensive components.
Initial checks

What to check first

  • See whether the brake lights stay on too long or cruise refuses to set immediately, because those clues fit a high brake input.
  • Inspect switch installation and pedal stop position before assuming the switch failed electronically.
  • Check for recent replacement parts because an incorrect switch or poor adjustment can create a brand-new P0573.
Driving risk

Can you keep driving?

P0573 often still allows driving, but it can disable cruise and may leave brake lamps behaving incorrectly. That makes it more than a cosmetic code.

Moderate urgency: This code often allows short-term driving, but the right fix usually comes faster when you diagnose it early instead of waiting for more codes.
Symptoms

Common symptoms

  • Reduced Power
  • cruise control will not set
  • brake lights may stay on
  • check engine light with brake switch high input
  • vehicle thinks brake is applied
Likely causes

Common causes behind this code

  • Brake-switch A circuit shorted to voltage or held high in the harness
  • Brake switch stuck in the applied state or installed in the wrong position
  • Pedal or bracket adjustment issue keeping the switch partially engaged
  • Connector fault or aftermarket switch mismatch altering signal behavior
  • Module-side interpretation problem caused by unstable feed voltage

Cause phrases often tied to this code: short to voltage, stuck brake switch, bad adjustment, connector issue, wrong switch installation.

Diagnostic order

Suggested workflow

  1. Verify whether the system thinks the brake is applied all the time by checking scan data and brake-lamp behavior.
  2. Inspect switch position, pedal free play, and bracket integrity.
  3. Check for a short-to-voltage or abnormal feed on the brake-switch circuit.
  4. Confirm correct part number and installation style if the switch was recently replaced.
  5. After repair, verify cruise operation and normal release state every time the pedal is untouched.
Avoid guesswork

Common mistakes

  • Installing a new switch without setting it correctly against the pedal stop.
  • Ignoring brake lamps that stay on intermittently because the problem seems minor.
  • Blaming the PCM when a simple switch-position issue is holding the signal high.
Repair path

Practical fix guidance

  • Correct the high-input cause by repairing the switch, wiring, adjustment, or installation problem.
  • Retest with the pedal released and applied multiple times to confirm the input transitions cleanly.
  • If the battery was drained by lamps staying on, verify voltage stability after the switch fault is fixed.
Vehicle context

Affected brands in this MVP

Brand hubs help broaden internal linking now and can evolve into make-specific diagnostic notes later.

Aliases and common searches

English phrases tied to P0573

Useful when the driver knows the wording but not the exact DTC yet.

  • brake switch a circuit high
  • brake pedal switch high input
  • P0573 brake switch high
Related search intent

Queries this page can answer naturally

  • P0573 code meaning
  • what does P0573 mean
  • brake switch A circuit high
  • P0573 cruise control issue
FAQ

Quick questions about P0573

Can P0573 keep the brake lights on?

Yes, depending on the platform and the exact switch failure mode.

Why does cruise control care about P0573?

Because the system must trust the brake-applied signal to engage and cancel cruise safely.

Is P0573 always electrical?

No. A misadjusted or misinstalled switch can create the same high-input story.