Volvo Park assist unavailable error message. Ways to fix this

A lot of owners of new Volvo vehicles that were made after 2018 and up to now, keep getting this nasty error message telling them that the Park Assist feature is unavailable. Some drivers just put up with this and park their vehicles on their own. But I believe you shouldn’t get attacked by those error messages when you own such a car.

The “Park Assist Temporarily Unavailable” error message often means that the auxiliary or main battery in your Volvo is drained or the BMS is malfunctioning. BMS stands for Battery Management System and it controls the condition of the batteries. Also, your Park Assist relies on the auxiliary battery in most new Volvo cars that’s why the system often fails along with the Start/Stop feature.

Here’s what I will cover in this article:

1. Why do you see the Park Assist Unavailable message in your Volvo?
2. What’s the auxiliary battery and where is it located?
3. Can you charge the start/stop battery in your Volvo?
4. Is this covered by the Volvo warranty?
5. Can you safely drive when your Park Assist is unavailable?

What does “Park Assist Temporarily Unavailable” mean?

If you see this error message in your Volvo, most likely, your Park Assist feature will not work. So, the vehicle will not find the proper place or parallel parking and will not steer the car for you into this place. For some drivers, it’s OK because they never use this feature while some others will be disappointed when they lose this option.

Now, you may have noticed that almost always the “Park Assist” message comes accompanied by the Start/Stop error. It’s important to know that the park assist and the start-stop feature in your Volvo are powered by the auxiliary battery or support battery. They never rely on the main battery that is used mainly for starting the engine.

Here’s what may happen:

• once you see these two errors, you may understand that the support battery is not feeling well;
• it may be drained because of city driving, stop-and-go traffic, and extensive use of start-stop feature;
• also, this battery may be drained because the main battery is dying and the BMS puts all the charge into the main unit;
• another possible option is the glitch in the BMS system that controls the work of both batteries, the system may need reset;
• once something goes wrong with the support battery, the BMS sees this and turns off the start-stop and the park assist.

Your auxiliary battery is charged with the help of the alternator. But it’s not vitally important for the vehicle, so it will get the proper charging after the main battery is fully charged. So, if you usually drive short distances, your vehicle just can’t charge the support battery properly and this leads to its quick death.

It doesn’t mean that when you see start-stop and park assist errors in your Volvo, the support battery needs to be replaced immediately. In the majority of cases, you just need to understand why it is drained.

Please keep in mind that if the “Park Assist Temporarily Unavailable” message appears alone, it may mean that the cameras or sensors are dirty and the system can’t safely work.

Where is the auxiliary battery in your Volvo?

The auxiliary battery is placed in different locations in various Volvo models. In the S60, you will find it under the plastic cover between the engine compartment and windshield. In the XC40, the auxiliary battery is placed behind the front bumper and the best way to get to it is to take off the driver’s side fender liner.

But before you take your tools and rush to take your Volvo apart, you should know that the auxiliary battery is not the only culprit of the Park Assist error message. You may start checking other units that are easily accessible.

Can you charge the auxiliary battery in a Volvo car?

Yes, you can charge it. But not every type of charger is good for it. This is the AGM battery and you should charge it with an AGM charger. Usually, there is a 10 Ah 12V support battery in Volvo cars and it will take just a couple of hours to gently charge it.

But if your support battery dies after 1-2 years of driving the car, there may be some other problem that you may need to check first.

For example, the faulty BMS may be not charging the aux battery and this leads to its premature death. Or the main battery is old and weak which makes the BMS use all the available power for charging the main unit and trying to keep it alive.

I would start by checking up the main battery, then I would use a code scanner to see if BMS is failing, and only after that I would get to the support battery and see if it needs charging or replacement.

How can you reset the BMS system?

The battery management system can be reset in two ways: by disconnecting the battery for several minutes or by a scanner. Of course, I recommend doing this with a scanner because it reprograms the BMS system and relearns it to work well with the remaining charge of both batteries. But for this, you will need to go to a trusted garage or to the Volvo dealer.

If you decide to disconnect the battery to reset the BMS, you will need to disconnect both the main and the support battery. It’s a challenging task because even getting to the support unit is not that easy.

Anyway, if you decide to do this, always disconnect the negative terminal first, then the positive. After both units are disconnected, press a honk or turn on some light to use the residual power and wait for 1-2 minutes. After that, connect the batteries – first positive, then negative terminals.

If the DIY reset didn’t work, you will anyway need to go to a good garage.

Is it covered by the Volvo warranty?

Actually, bad batteries aren’t covered by the warranty. Usually, a Volvo rep will tell you that the car doesn’t cover enough miles to charge the battery, so the support unit went bad and needs replacement. Depending on the country, the aux battery for a Volvo vehicle will cost you 80 to 200 euros.

But if you cover the average distance in your car and the aux battery is low after just 1-2 years, you may ask Volvo if they want to replace the battery for free. According to several messages in European forums, this is possible.

If the car is older than 3 years and or is out of the warranty mileage, you will have to buy the battery for your own money. Of course, I recommend a non-OEM replacement because it will cost you twice cheaper and will still work completely well.

Can you still drive your Volvo when Park Assist is Unavailable?

If your Volvo tells you that the start-stop and park assist functions are not available, you may start thinking that something is wrong with the vehicle. Maybe, you should just stop it and call road assistance? But no, not in this case. You can continue driving and you can even ignore the problem if you don’t care about the park assist and the start-stop features.

Here’s why:

• those features are not safety functions, so you may get along without using them at all;
• they both rely on the aux battery, but even if it’s completely dead, your car will function;
• after you drive for long enough, the error may disappear because both batteries may be charged by the alternator.

So, you can keep driving but you shouldn’t completely ignore the problems. It may tell you about the main battery problems, BMS issues, and also alternator problems that affect the reliability of your car. On one bad day, you may get stranded with no electrical power in your car and no chance to start the engine.

To wrap up

Although the Park Assist and the Start/Stop features are not extremely important, it’s always unpleasant to get those error messages in your Volvo. After reading this article, you know what you can do and when you should contact the dealer to solve the problem. When you see the “Park Assist Temporarily Unavailable” in your Volvo, just follow the recommendations given above and you will solve the issue easily.