The annoying “Park Assist Blocked” warning light. If you drive a fairly new vehicle, you may have seen this message (or a variant) pop up in your dashboard display. But what does it mean and should you worry?
In this article, we’ll explain what triggers the “Park Assist Blocked” warning, what it means for your car, and most importantly, what you can do to get this pesky problem fixed.
What is Park Assist?
Over the past decade, auto manufacturers have worked tirelessly to equip their vehicles with the latest and greatest in driver-assistance features. As a result, vehicles have become safer to use, when piloted by detail-oriented drivers, educated in the use of such technology.
One of the most helpful and beloved of these driver-assistance features is Park-Assist.
Park Assist provides drivers with audio and visual cues that assist them in safely parking their vehicles. In almost every case, an audible alarm is sounded when you manipulate your vehicle in a manner that positions it too closely to an obstacle of one type or another.
In many cases, external cameras are also used to provide a visual of such obstacles.
The latest versions of park-assist now feature the ability to automatically apply a vehicle’s brakes, should you find yourself close enough to a fixed obstacle that a collision appears imminent. This, in turn, has virtually eliminated parking-related collisions, among late model vehicles, thereby saving thousands in insurance claims.
What Does a “Park Assist” Warning Mean?
Typically, the issuance of a “Park Assist Blocked”, Park Assist Unavailable”, “Park Assist Off”, “Park Assist Malfunction”, or other similar message means that a vehicle has identified a malfunction that would prevent it from utilizing its integrated park assist function in an unimpeded manner.
In most cases, this means that one or more inputs are unavailable that typically allow the park assist system to make intelligent calculations regarding the proximity of obstacles to the affected vehicle itself.
Due to the potential for a collision under less than ideal circumstances, a vehicle will deactivate all park assist functions, thereby mitigating unnecessary risk. In many cases, the only way to reactivate the park assist function is to address the underlying issue itself, or to perform a hard reset of the offending fault.
However, if the latter of these options is pursued, the above-mentioned park assist lockout is likely to reoccur as soon as the offending fault is relogged.
Warnings related to parking assist sensors are quite common. Car manufacturers have even issued Service Bulletins (like this one from GM) in regards to this issue.
There are several potential causes of a reoccurring “Park Assist Blocked” message. Understanding these potential causes can assist you in quickly narrowing down the cause of your vehicle’s current issues, and restoring park assist functionality.
The following are several of the most common causes of park assist faults. Some vehicles may even display a more specific message like “Park Assist – Clean Sensor” but the actual cause may be entirely different.
#1 – Dirty Sensors
Fortunately, the most common cause of a “Park Assist Blocked” message is dirty sensors. This often comes as the result of dirt, mud, or gravel dust obstructing one or more sensors as a whole.
In this case, the only viable solution is to thoroughly clean each of your vehicle’s sensors.
#2 – Heavy Rain
If you have ever experienced a park assist failure while driving in heavy rain, what you witnessed could be described as fairly normal.
If perception becomes heavy enough that it impedes a park assistance sensor’s range of detection, a resulting “Blocked” message will often be displayed.
#3 – Excessive Speed
Many vehicles are programmed to only allow the use of park assistance features under certain speeds, as a matter of safety. While this interlock is not applied to all park assistance functions, it is prominent enough that it bears discussion.
If you are backing at a relatively high rate of speed, and you receive a “Park Assist Blocked” message, try slowing your pace for better results.
#4 – Damaged Sensors
If your vehicle has recently been in a collision of any type, do not be surprised if park assist functionality is lost. This is especially true if any damage has been sustained to a vehicle’s front or rear bumpers.
The sensors used by most park assistance systems tend to be relatively delicate, and susceptible to damage.
#5 – PCM Malfunctions
Though extremely rare, a vehicle’s PCM can fail, preventing it from effectively computing data relayed from individual park assistance sensors. As a result, park assist functionality is often lost.
However, you should definitely rule out all other possibilities before condemning a PCM for such issues.
Where Are Park Assist Sensors Located?
In most every case, vehicles utilizing park assist functions feature several ultrasonic sensors positioned within both their front and rear bumpers. Each sensor is mounted and articulated in a specific manner that provides the maximum angle of detection.
This ensures that no obstacles in a vehicle’s path go undetected, and that safety is held paramount in every situation. Typically, each above-mentioned sensor features a dedicated detection range of 4-8 feet.
How to Reset a “Park Assist Blocked” Message
The exact procedure for resetting a vehicle’s “Park Assist Blocked” message differs from one model of vehicle to the next. Because of that, it’s important to look up the exact reset procedure provided for your particular make/model of the vehicle.
In any event, this warning message should be able to be reset through an interactive menu accessed with the use of a quality automotive scan tool.
In most cases, a general reset of a vehicle’s park assist function can be achieved by cycling this option on/off on your vehicle’s preferences menu. In doing so, the system re-initializes, checking all of its inputs in the process.
Assuming that the issue that your vehicle previously experienced was intermittent in nature, this should re-establish the park assist function.
Is It Safe to Continue Driving?
It IS safe to continue driving, in light of a “Park Assist Blocked” message. Though park assist functionality will be void, you can continue driving your vehicle as you normally would, as no other vehicle systems will be affected.
You’ll simply be required to park manually without any additional audio or visual cues, as they otherwise would when driving a non-park assist equipped vehicle.
Is “Park Assist Unavailable” on Teslas the Same Thing?
Yes, in many ways, the “Park Assist Unavailable” message often displayed by various Tesla models, is one in the same with “Park Assist Blocked” warnings logged by other vehicles.
Simply put, a fault within the parking guidance system has caused all park assistance functions to be deactivated. This occurs with Teslas for much the same reason as it does other vehicles.
The one exception is that Tesla vehicles have proven prone to displaying this message immediately after downloading various updates, for reasons largely unknown.