"Stop Safely. Vehicle Will Shut off Soon" in Jeep. What's This?

Modern Jeep vehicles can surprise you with several pretty common yet very mysterious problems. When you see your Jeep saying "Stop safely. Vehicle may shut off soon", you may start panicking. And you actually should because you are about to get stranded unless you quickly locate the problem.

Stop safely, vehicle will shut off soon message highlights

• Common reasons:transmission problems, control modules faulty
• How to fix:take it to the dealer, there are no DIY fixes
• Possible consequences:transmission may be dead
• Priority level:High
• Can you drive?Carefully
• DIY repair:Impossible
• Repair price range:$500-$12,000

Here's what I will tell you today:

• What are the functions of two batteries in your Jeep?
• What are the common reasons for this error message?
• What can you do immediately when this happens to your Jeep?
• Will changing the batteries help you solve the problem?

Let's get started!

Two batteries in modern Jeep vehicles - what for?

Cars with the start-stop system that have only one 12V battery prove to be pretty unreliable. Their batteries are AGM or EFB and it's hard to check whether they are dying. They will almost always show 12.4-12.5 volts and then suddenly die in the middle of nowhere not allowing you to start the car.

So, car manufacturers now massively turn to two-batteries systems. They install the auxiliary battery and split the functions between two power units. The first one just cranks the engine and the other one powers all the accessories, safety systems, etc.

So, basically, this helps your computer, electronic control modules, and other functions stay alive when the engine is stopped by the start-stop system. Also, this releases some load from the cranking battery to let it work for longer times (as claimed by manufacturers).

Unfortunately, in Jeeps starting from the 2018-2019 model years this system has proven to be pretty problematic. One of the ways it can malfunction is by sending the error message on the dash saying "Stop safely. Vehicle may shut off soon".

What are the common reasons for this message?

When you see that your Jeep is saying it may shut off soon, you may panic. Actually, the car may or may not shut off depending on the initial reason for this error message popping up. While in some cases this may be a problem and the car will actually turn off and won't start, in many cases, this is just a random message that will go away soon.

Here are the most common reasons to pay attention to:

1) One of the batteries is degraded heavily

Both batteries have a certain lifespan. If you bought your Jeep in 2019 and still use both original batteries, this is most likely the problem with the vehicle. While the batteries can still show normal voltage in all situations, they may be pretty weak under any serious load. So, when the engine shuts off and all the load goes to the auxiliary battery, it may eventually fail and its voltage may drop.

Check the batteries using professional diagnostic stations in battery stores or in repair shops. This will help you see whether the voltage drops heavily under some load. If it actually drops, you can try recharging the battery using the proper charger. Or you may change it with the new one, especially if the old battery is 4-5 years old.

2) One battery doesn't charge another one

The charging system in modern Jeep vehicles is pretty complicated. The alternator charges the cranking battery whenever the engine is on. There is a smart link that connects that crank battery with the auxiliary one. It opens when the crank battery is fully charged and it then lets the crank battery give some charge to the auxiliary one.

If you drive in stop-and-go traffic, the cranking battery will get quite many problems and the alternator will charge only this unit. So, your auxiliary battery will eventually be without any support. In such cases, it will need to be recharged manually from time to time. Of course, the battery will most likely die quite soon from deep discharge and this can trigger the "Stop safely. Vehicle may shut off soon" message.

3) The smart link between batteries is bad

The link between batteries that allows the auxiliary one to charge is not as smart as Jeep thought it would be. Very often, it goes bad in Jeep vehicles and just messes up everything in the charging system. This means that you will need professional help to check the connections and the software that controls this system.

4) The alternator isn't working properly

For any modern car, fast battery recharging is super important. If your alternator doesn't produce the proper voltage, you may eventually find both batteries degraded and destroyed by deep discharge. Sometimes, you will not see any warning lights or messages until the situation becomes hazardous.

5) Fuses or relays

The fuse block that is connected to the charging system and batteries is a tricky thing in modern Jeep vehicles. I've seen this problem in the Grand Cherokee and Compass, so I can conclude that any Jeep vehicle with two batteries can have this. The relay that connects two batteries with each other can easily go bad and you will have your auxiliary battery dead pretty soon.

Or there may be blown fuses in the fuse box and it will not properly control the charge of the batteries degrading both of them. Unfortunately, this is not a DIY task to check the relays and fuses unless you are a good car technician.

6) Mysterious software problems

I've seen several Jeeps with this message and the problem seemed to be impossible to catch. The message popped up when the aux battery was at about 11 volts. Then, the charging system kicked in and the voltage went back to normal and the message disappeared. Oddly, I couldn't locate the problem.

If you are offered to replace the alternator, don't agree to pay for that - it's obviously not the issue. There are some problems with the regulators or some software that controls the charging process. After several software updates and resets, the problem went away and hasn't returned in those cars that I had experience with.

What should you do when you see this message?

Well, whenever you see the "Stop safely. Vehicle may shut off soon" message, you should actually stop the car in a safe place because it may shut off due to charging system issues. I would try disconnecting both batteries for a while and then connecting them back.

Start with the cranking battery and then move on to take off the cable from the negative terminal of the aux battery (usually located under the fuse box in the engine bay). After you disconnect both batteries, press the honk to use all the power in the system. Wait for several minutes and connect both batteries.

You may try driving now as the system was reset and may now have much more reliability in it. But if the message reappears on the dash, it's time to stop and try to find professional help. If your car still works, you can slowly drive on the right side of the road with your emergency lights on. Maybe, you will get to the dealership without paying for a tow truck. But if the traffic is active, don't risk and just find a way to tow your vehicle to the repair shop.

Will changing the batteries always help?

When you are in the dealership, you may get one simple problem: lack of proper diagnosis. Dealer mechanics don't care much about your money. So, if your car is under warranty, you may allow them to do anything that you don't need to pay for. If the warranty is over, be careful - they may just replace one part after another till they find the problem. This may eventually cost you a fortune.

Changing batteries will not always help. Well, it may help for some time till the new aux battery is degraded again. But ask the mechanic to test the charging system, to measure the voltage on batteries when the engine is on, etc. Also, ask them to check the fuses and relays that control the charging system. Otherwise, you can just throw a lot of money away by changing the parts that are still OK.

Final thoughts

Although the "Stop safely. Vehicle may shut off soon" error message seems to be a ghost problem that is very hard to locate, there are pretty simple reasons for it: the batteries and the charging system. Checking both factors isn't that easy, especially if you don't have the proper equipment for that. So, you may need to get some professional help.

But in the dealership, be careful and don't allow mechanics to change everything without any warranty for good results. Usually, saying that you won't pay if the manipulations don't resolve the problem does some magic.

If you have experience dealing with this error message in Jeep vehicles, please write in the comments below and share your solutions with other Jeep owners!