P0573 Code: Brake Switch “A” Circuit High

Aside from managing your vehicle’s  engine, your powertrain control module (PCM) also controls its sensors and switches. They help your PCM engage various vehicle features, such as adaptive cruise control, which can greatly contribute to your comfort. Your brake switch plays a key role in activating your adaptive cruise control. If your PCM detects brake switch malfunction or failure, it may trigger a P0573 code. 

Here’s what you need to know if you scan your vehicle and the OBD code P0573 pops up:

What Does the P0573 Code Mean?

Diagnostic Trouble Code (DTC) P0573 represents “Brake Switch ‘A’ Circuit High.” This is also associated with adaptive cruise control issues. Code P0573 indicates that your brake switch isn’t properly sending information to your PCM.

Your brake switch works by sending signals to your PCM, so it can control various functions in your vehicle, such as activating your brake lights, releasing the shift lock actuator, and it even plays a part in how the transmission downshifts, among other things.

The  brake pedal input also cancels cruise control, and may keep the cruise from operating at all.

If the PCM cannot properly detect information from your brake switch, a code P0573 may show up. This code is linked to brake switch issues and adaptive cruise control malfunction, so it’s best to resolve it immediately.

P0753 on Some Ford Vehicles

Ford describes the P0573 code as follows. BPP stands for “brake pedal position” switch:

P0573 sets when the brake switch is stuck in the OFF position.

• BPP circuit open
• BPP circuit short to voltage
• BPP circuit short to ground
• Stoplamp circuits open
• Stoplamp circuits short to voltage
• Stoplamp circuits short to ground
• Damaged brake switch
• Incorrectly adjusted brake switch

Note: The definition of code P0573 may be different depending on the vehicle manufacturer. Consult the appropriate repair manual or repair database for the exact code definition.

What are the Possible Causes of the P0573 Code?

Here’s a list of common causes of a P0573 code:

• Dirty or faulty brake switch
• Wiring problems
• Failing PCM

What are the Common Symptoms of the P0573 Code?

The P0573 Code may be associated with a wide range of symptoms. Here are the most common signs to look out for:

• Erratic or inoperative adaptive cruise control
• Malfunctioning or failing brake lights

How to Diagnose the P0573 Code

You can monitor the brake light switch input using a scan tool while operating the brake as an initial test. On most vehicles, the brake switch doesn’t actively close the circuit to carry current, rather it sends a signal to one or more modules.

Take note, however, that diagnostic trouble codes, including code P0573, are generally difficult to deal with. You may want to try sorting them out on your own, but it may be too technical for you. We recommend consulting a mechanic for an expert diagnosis. If you’d like to learn more about code P0573, grab your vehicle’s owner’s manual and check out these videos:

How to Fix a Code P0573

There’s no one solution to fix problems that trigger OBD codes. Efficiently diagnosing and troubleshooting OBD codes may require extensive training as well as many years of experience. The best way to resolve trouble codes is to ask a mechanic for help.

However, you can try working on your vehicle’s trouble code by doing some comprehensive research. After scanning your vehicle, you need to inspect any complications linked to it. After you take note of all the necessary details, you can determine the cause and seek advice from reliable online resources for the next steps that you should take.

For code P0573, you’ll need to consult your owner’s manual, because it may have manufacturer-specific indications. Correct information for a P0573 code in a Chevy may not apply for a Kia. If it’s too difficult to troubleshoot, don’t hesitate to ask for help from a certified mechanic.