The Annoying “Park Assist Blocked” Light. If you drive a relatively recent vehicle, you may have seen this message (or a variant) appear on your dashboard screen. But what does it mean and should you be concerned?
In this article, we will explain what triggers the “Park Assist Blocked” warning, what it means for your car, and most importantly, what you can do to resolve this annoying issue.
What is Park Assist?
Over the past decade, car manufacturers have worked tirelessly to equip their vehicles with the latest and most advanced driving assistance features. As a result, vehicles have become safer to use when driven by detail-oriented drivers trained in using this technology.
One of the most useful and appreciated driving assistance features is Park Assist.
Park Assist provides drivers with audio and visual signals that help them park their vehicle safely. In almost all cases, an audible alarm triggers when you maneuver your vehicle in a way that positions it too close to an obstacle of one type or another.
In many cases, external cameras are also used to provide a visual image of these obstacles.
The latest versions of park assist now offer the ability to automatically apply a vehicle’s brakes if you get close enough to a stationary obstacle that a collision seems imminent. This, in turn, has virtually eliminated parking-related collisions among the newest vehicles, thereby saving thousands of 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 any other similar message means that a vehicle has identified a malfunction that would prevent its integrated park assist system from operating seamlessly.
In most cases, this means that one or more inputs are unavailable, which normally allows the park assist system to perform intelligent calculations regarding the proximity of obstacles relative to the vehicle itself.
Due to the risk of collision in less-than-ideal circumstances, a vehicle will disable all park assist functions, thereby mitigating unnecessary risks. In many cases, the only way to reactivate the park assist function is to resolve the underlying issue itself or perform a hardware reset of the fault in question.
However, if the latter of these options is chosen, the aforementioned park assist lockout is likely to recur as soon as the fault in question is re-registered.
Park assist sensor warnings are quite common. Car manufacturers have even issued service bulletins (like this one from GM) regarding this issue.
Common Causes
There are several potential causes for the appearance of a recurring “Park Assist Blocked” message. Understanding these potential causes can help you quickly identify the reason for your vehicle’s current issues and restore park assist functionality.
Here are some of the most common causes of park assist failures. 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 is often due to dirt, mud, or gravel dust obstructing one or more sensors entirely.
In this case, the only viable solution is to thoroughly clean each of your vehicle’s sensors.
#2 – Heavy Rain
If you have ever encountered a park assist failure while driving in heavy rain, what you witnessed could be described as fairly normal.
If the precipitation becomes strong enough to interfere with a park assist sensor’s detection range, a “Blocked” message will often appear.
#3 – Excessive Speed
Many vehicles are programmed to allow the use of park assist functions only at certain speeds, for safety reasons. Although this lockout does not apply to all park assist functions, it is significant enough to warrant discussion.
If you are reversing at a relatively high speed and receive a “Park Assist Blocked” message, try slowing down your pace for better results.
#4 – Damaged Sensors
If your vehicle has recently been involved in a collision of any kind, do not be surprised if park assist functionality is lost. This is especially true if a vehicle’s front or rear bumpers have been damaged.
The sensors used by most park assist systems tend to be relatively fragile and prone to damage.
#5 – PCM Malfunctions
Although this is extremely rare, a vehicle’s PCM can fail, preventing it from effectively calculating data relayed by individual park assist sensors. As a result, park assist functionality is often lost.
However, you should absolutely rule out all other possibilities before condemning a PCM for such issues.
Where Are the Park Assist Sensors Located?
In most cases, vehicles using park assist functions are equipped with several ultrasonic sensors positioned in their front and rear bumpers. Each sensor is mounted and articulated in a specific way that offers a maximum detection angle.
This ensures that no obstacle in a vehicle’s path goes unnoticed and that safety is paramount in every situation. Typically, each of the aforementioned sensors has a dedicated detection range of 4 to 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 vehicle model to another. For this reason, it is important to research the exact reset procedure provided for your specific vehicle make/model.
In any case, this warning message should be resettable via an interactive menu accessible using a quality automotive scan tool.
In most cases, a general reset of a vehicle’s park assist function can be achieved by toggling this option in your vehicle’s preferences menu. Doing so resets the system, thereby checking all its inputs in the process.
Assuming the issue previously encountered by your vehicle was intermittent in nature, this should restore park assist functionality.
Is It Safe to Continue Driving?
It is safe to continue driving in light of the “Park Assist Blocked” message. Although park assist functionality is canceled, you can continue to drive your vehicle as you normally would, as no other vehicle systems will be affected.
You will simply need to park manually without any additional audio or visual signals, as you would otherwise when driving a vehicle not equipped with park assist.
Is Unavailable Park Assist on Tesla the Same Thing?
Yes, in many ways, the “Park Assist Unavailable” message often displayed by various Tesla models is one and the same with the “Park Assist Blocked” warnings recorded by other vehicles.
Simply put, a malfunction in the parking guidance system has caused all park assist functions to be deactivated. This happens with Teslas for the same reason as with other vehicles.
The only exception is that Tesla vehicles tend to display this message immediately after downloading various updates, for largely unknown reasons.