P0573 code meaning
Brake Switch A Circuit High
What P0573 means
Brake switch A is the brake light switch or its signal to the engine module. The module needs it to cancel cruise control and for brake-throttle override, stop-start, idle control and the shift interlock. As cruise control is simply switched off, CARB treats such faults as emission-neutral – usually without warning lamp. P0573 means the switch signal stays high – always pressed – although the car is not braking. Ford diesel checks over 40 accelerations, Ford gasoline over 25 brake applications without warning lamp; GM in the Saab 9-4X compares the input with the body module, 8 of 10 samples over 2 s. Typical are a switch stuck closed, a pedal not fully returning or a short to positive. Cruise control is locked out.
P0573 at a glance
- Check engine lightUsually not
- Emissions testNot an emissions code
- Limp modeNot expected
- Repair difficultyEasy, DIY possible
- Typical labor0.3 to 1 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P0573
- Brake lights permanently on
- Cruise control unusable
- Shift interlock disturbed
Common causes of P0573
- Most likelyBrake light switch stuck closed or misadjusted (pedal stop buffer missing)
- PossibleBrake pedal not returning fully (floor mat, return spring)
- PossibleSignal line shorted to positive
- Less likelyBody or engine module
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Brake switchBrake light fuseSwitch wiringEngine control module
What each part of P0573 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 5 | Area: vehicle speed, idle control and auxiliary inputs. |
| 73 | The exact fault in that area. |
What to do next
- Note P0573 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P0573
What does P0573 mean?
P0573 means "Brake Switch A Circuit High". Brake switch A is the brake light switch or its signal to the engine module. It is a generic code, so it means the same on every make.
Is it safe to drive with P0573?
P0573 does not normally turn on the check engine light by itself. Watch for the symptoms above and have it checked soon.
Will P0573 fail an emissions test?
P0573 is not an emissions code, so on its own it usually does not fail an emissions test. Other stored codes or a lit check engine light still can.
How hard is P0573 to fix?
Difficulty: easy. A typical repair takes 0.3 to 1 hours of work. A careful DIY repair is possible with basic tools and a scanner.
Will P0573 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.