If you own a car, you will likely have come into contact with limp mode at some point in your driving experience.
Most modern cars have this feature installed as a self-preservation technique to protect the engine from further damage. But what exactly is limp mode?
Limp mode is a security feature that is included in the majority of newer build cars. It activates when the car identifies a fault in the transmission control or the engine to protect the mechanics of your vehicle from further damage.
Once activated, limp mode causes the functions of the car which are classed as ‘less important’ such as air conditioning, and features like this, to shut down and the speed of the car will be significantly reduced.
Once limp mode is activated, you should take your car to the garage so that the root cause of the problem can be fixed.
However, it is possible to bypass limp mode so that your car can continue to operate like normal until then, we’ll look at how you do this as well as how to prevent limp mode in this article.
Common Causes of Limp Mode
We’ve already covered that limp mode is activated when your car identifies an issue with the engine or transmission. This is quite a broad spectrum for errors to occur, but some common causes can activate limp mode.
If your car activates limp mode but you are uncertain why the reason may lie in one of these common causes.
The most common reason that your car may activate limp mode is because of a failure in your transmission system. The main issues that trigger this are bad solenoids or poorly adjusted links between the transmission system and the steering system.
If an error is identified within the transmission system, your car will activate limp mode to protect the transmission system from any further damage.
Another common cause is if there is an issue with your car’s battery. The battery powers the car’s computer system so if any issues occur with the battery this will impact the computer system and trigger limp mode.
A common issue that may trigger this is a battery acid leak. The acid leaking can cause damage to the wires which connect the battery and your car’s computer system. This issue isn’t actually a problem with the engine or the transmission, however, it can be misinterpreted as a transmission issue.
If your car activates limp mode but you don’t think there’s an issue with the transmission or the engine, this could be the cause.
Finally, another possible cause is a sensor malfunction. As newer models have come onto the market, manufacturers have started to include more sensors within the vehicle.
A lot of modern vehicles rely on sensors to control the transmission of the car and also the engine, with common sensors being the MAP, MAF, and speed sensor.
While these sensors operate normally most of the time, on occasion they can send incorrect signals to the car’s computer which can cause limp mode to activate.
How to Bypass Limp Mode
Now that we’ve covered the possible causes of limp mode, let’s move on to how you can bypass limp mode. Once this activates your car you should ideally take your car to the garage to identify the cause of the problem.
However, it can be taxing to drive your car in limp mode due to the reduced functions and speed, so it is usually easier to take your car out of limp mode before taking it to the garage. There are a few steps you should follow to move your car out of limp mode to enable you to drive your car like normal.
As soon as you notice your car has moved into limp mode, you should apply the brakes. Once you have reached a safe space, you should pull the car over and let the engine rest for at least 5 minutes. This allows the car’s computer to shut down and disable the system aids.
After 5 minutes has passed you should start the engine and shift gears until you reach the highest gear. This will allow you to identify if limp mode has deactivated or not.
Another way to bypass limp mode is through the use of a diagnostic scanner. The scanner will allow you to identify whether limp mode has been activated because of an ignition problem or because of a false alarm.
A diagnostic scanner will also allow you to identify if limp mode has activated because of a boost deviation in your vehicle.
A final way to bypass limp mode is through disconnecting the battery. Once you have stopped in a safe space you should pop the bonnet of your vehicle and take a look.
You should find the battery and disconnect all of its connections. This will reset the transmission memory, so when you reconnect the battery after 30 minutes, limp mode should have deactivated itself.
Of all the methods we’ve outlined, this is the most common and effective way to disable limp mode and allow you to drive your car like normal again.
How to Prevent Limp Mode
Now that you are aware of some common causes of limp mode, and also ways to bypass this when it occurs, it seems fitting that we look at ways to prevent limp mode from occurring.
Prevention is better than cure, and there are some easy ways you can use to reduce the likelihood of you having to deal with limp mode. Sometimes it will be unavoidable, but these easy steps can help prolong the time between your car going into limp mode.
Firstly, you should ensure you check the fluid levels of your vehicle regularly, ensuring you top them up when they are low.
You should also check the connections within your vehicle regularly, it is easy for wires to become loose so if you spot any of these you should tighten them. Finally, you must never avoid warning signs of an error in your car’s transmission.
One common sign of this is a slow gear shift, if this occurs you should check for further problems as this may mean your car is going to enter limp mode soon.
Summary
Limp mode occurs when your car identifies a potential fault in the engine or transmission system.
If this occurs you should take your vehicle to the garage to identify the problem, however, you can easily bypass limp mode to make the journey easier.