If your Tesla says “Vehicle May Not Restart”, it hints at a problem with the 12V battery, but I would dig deeper and look at the main battery cooling equipment. The actual problem depends on what other error messages and codes you see on the screen of your Tesla. And it’s not always that easy to see what sits behind this puzzle.
The meaning of the “Vehicle may not restart” warning
You may be quite surprised to see this message in an electric vehicle. OK, you can understand if your gasoline car says it won’t restart. Then, you will automatically think about the low battery and will charge or replace it. But how does Tesla start? It appears that your Tesla EV also has a 12V battery that is supported by the main EV battery.
This 12V battery is used for starting your car, supporting its life when needed, and also powering several important units in the car.
So, it’s quite possible that one day you may see the “Vehicle may not restart” error message in your Tesla car. Here’s what it can mean:
- the vehicle made a quick check and figured out that there is a problem that may prevent it from starting successfully;
- it triggered the message so that you could go directly to the dealership and have the issue solved by professionals;
- the problem may be with the 12V battery, EV battery, or some of the components that allow it to work;
- it doesn’t automatically mean that if you stop the car, you won’t be able to start it again, but there is the risk of such a scenario;
- also, if you keep driving the Tesla with this error message, it’s not uncommon to get a serious problem with expensive battery components.
To understand how serious the situation actually is, you need to read further and see the reasons that trigger this error message. For now, you just learned that this message means that there is a risk of your Tesla not starting the next time you will be going to drive it.
You may be surprised but the majority of functions in your Tesla are powered by the little 12V battery. These are lights, ABS-module, interior lighting, music, wipers, etc. In turn, this 12V battery is charged via a special converter using the power from the main battery. But the 12V battery in Tesla is used pretty heavily, so it can die much earlier than you expect.
What are the reasons for the “Vehicle may not restart” message?
Whenever your Tesla shows this message, you will think about the 12V battery. And, in most cases, you will be right. This battery is actually the culprit of this annoying error most of the time. But this is not the only possible reason, so keep reading to find out all the possible issues triggering this message.
Here they are:
1. The 12V battery is low or dying
Without the properly working 12V battery, your Tesla is dead. You will not be able to start or drive it. It’s extremely important to know when to replace this battery or when to charge and maintain it to prolong its life.
While the average lifespan of the battery in a gasoline car is 4-5 years, in your Tesla, it will only live about 3 years. After that, it’s impossible to bring it back to life. You will just need to replace the battery.
If it doesn’t hold charge anymore and provides the car’s electrical system with a low voltage current, your Tesla may get several other issues. Some of the consequences will be quite costly to repair, so just don’t ignore this problem.
To make sure it’s the battery, try the following:
- locate the 12V battery in your Tesla car;
- measure its voltage without any load – it should be about 12.5 to 12.7 volts;
- then turn on lights and wipers and measure the voltage again;
- if you see that the voltage now drops to 11 volts or even lower than that, the battery is completely dead.
Replacing the 12V battery should fix this problem in your vehicle. Of course, this is not the only problem that may trigger the message, so keep on reading.
2. The DC-DC converter issues
Your 12V battery is charged using the power from the main battery via a special converter. It’s worth checking it because if the small battery doesn’t get charged, it will die very soon and will most likely ban you from using the car.
Converters usually live a lifetime of the Tesla, but they may be affected by water or damaged in a car accident. So, have a look at it, look at the connections, and maybe check if it gives some voltage to the 12V battery to try and charge it.
3. The main battery issues
Your Tesla’s main battery is fitted with a special electronic control system that is so smart that it’s hard to describe how it works. But if the battery charge is low, it may cut off all the power recipients including the 12V battery. If this happens for a long time, the small battery may be completely drained.
Of course, in this case, you will also see other error messages along with the “Vehicle may not restart” alert. Usually, this may happen with older Tesla vehicles whose batteries are about to die.
4. Main battery cooling system
When you drive your Tesla, the battery is heated. It means that it needs some cooling. While other manufacturers use different ways of natural air cooling, Tesla uses liquid cooling which needs some energy. It’s efficient and good until something is broken.
There is a pump that sends coolant to the cooling system of the battery. In some Tesla cars, this pump is pretty faulty and can fail at any moment. You can’t check it, you will need professional help for this.
Driving your Tesla with a failed battery cooling system is not recommended as it may lead to all kinds of disastrous things. Usually, the car will just shut down to protect the main battery from quick degrading or even igniting.
5. Software or wiring problems
A lot of cases are so tangled and hard to diagnose that people end up going to the dealership and they find out that some connectors in the control module were lost or the software glitched and needed hard reset.
This is not uncommon for a Tesla to develop wiring or connection issues, especially if the car has been in contact with water. It’s not necessary that your Tesla was flooded. It’s enough to spill some coffee in a certain spot to get the problems.
Also, software issues are possible and you may know that Tesla software is not the most stable in the world. It will glitch and sometimes pretty much. Though, it can be cured with a simple reset, most of the time.
What should you do when you see the “Vehicle may not restart” message?
If your Tesla says “Vehicle may not restart”, the good thing to do is to call Tesla Assistance immediately. Don’t shut off the car because it actually may not restart.
Your Tesla Assistance will ask you about any symptoms, other messages, and codes. Then, they will tell you what to do. Most often, they will ask you to immediately come to the nearest Tesla dealership and will provide your car with some checkups.
I was surprised to know that even 7-year-old Teslas can sometimes be repaired under warranty when it comes to software problems or some common malfunctions. So, you should certainly give it a try and maybe you will solve the problem with no extra costs.
Can you drive when your Tesla says “Vehicle may not restart”?
I wouldn’t recommend you drive further ignoring the problem. Yes, this message will quickly go to the “inactive” folder, but you should understand that the dying 12V battery or malfunctioning main battery cooling system may quickly destroy the car and make a lot more harm than you may think.
So, driving it further is OK in that case only if you called the dealership and they told you to come directly to them. In some cases, the guy from the Assistance may tell you to park your car in the nearest safe place and wait for the road assistance to come to you.