P0573 OBD-II Trouble Code: Cruise Control/Brake Switch A Circuit High

P0573 code definition

When the PCM stores the P0573 code, it’s because it has discovered an electrical malfunction affecting your vehicle’s cruise control brake switch “A” circuit.

What the P0573 code means

Your vehicle’s PCM works in tandem with the cruise control module to automatically control its speed. If the PCM receives input that alerts it that the vehicle can no longer control its own speed, it will initiate a test of the entire cruise control system. P0573 code gets stored once your vehicle’s PCM senses an abnormal resistance/voltage level in the cruise control brake switch circuit during this test. That feedback essentially tells it speed cannot be controlled and thus cruise control must be prohibited.

What causes the P0573 code?

By far, the most common reason for a P0573 code being stored is that the cruise control switch failed. Open or shorted circuitry inside the cruise control buttons because of spilled liquids actually occurs fairly often. This is usually enough to keep the circuitry from performing normally and, thus, triggering the P0573 code.

Other causes that may be responsible include:

That last one is probably the least likely reasons as something fairly severe usually has to happen before a fuse is blown.

What are the symptoms of the P0573 code?

The most obvious symptom of a P0573 code is that the cruise control on your vehicle will no longer work. You may also get a Check Engine Light, but that’s not always the case; a lot of models require as many as three drive cycles of the P0573 code before it will activate the light to alert you.

We just mentioned that, although rare, blown fuses can cause the code. But they can also be a symptom of the P0573 code too.

How does a mechanic diagnose the P0573 code?

Most mechanics will begin by taking an OBD-II scanner and a digital ohmmeter to perform the initial diagnosis. Then, they’ll proceed to check your vehicles wires, connectors, and other electrical components to check for some of the symptoms we mentioned earlier. They’ll also look for any signs of spilled liquid.

Common mistakes when diagnosing the P0573 code

Rare though they may be, it’s a good idea to check for fuses that may have blown either before or after the P0573 code was stored. This should be done before any serious repairs or replacements occur because both often happen due to problems that stem with a blown fuse. By simply addressing the fuse, mechanics can avoid a lot of time-consuming, expensive repairs that wouldn’t be necessary.

How serious is the P0573 code?

If you enjoy using your vehicle’s cruise control setting, then it’s essential that you have problems related to a P0573 code addressed right away or you won’t be able to use it. Of course, if a blown fuse is part of the problem, you’ll be relieved if you catch it early by taking your vehicle to a qualified mechanic. A blown fuse could be the beginning of a number of other problems too.

What repairs can fix the P0573 code?

The good news is that repairing your vehicle should be fairly simple. Generally, all you need to do is fix the damaged wires or connectors causing the problem. Worst case scenario, the blown fuse has to be fixed.

Additional comments for consideration regarding the P0573 code

Remember that, for some of you, there won’t be a Check Engine Light – at least not right away – if a P0573 code is stored. However, that doesn’t mean you have to wait to bring your vehicle in. If your cruise control isn’t responding, there’s clearly a problem and it could potentially become worse if you wait too long to get help.

Need help with a P0573 code?

YourMechanic has a team of certified mobile mechanics who can meet you at your home or office – whichever you prefer – to diagnose the problem affecting your vehicle and provide necessary and affordable prepares. Either fill out this online form or just give us a call at 1-800-701-6230 to speak with a service advisor. We’ll give you a free quote and schedule your appointment.