Do you ever experience driving your truck when suddenly there is a loss of power, and you notice the warning lights on your dashboard start to blink?
These scenarios are signs that your truck experienced limp mode.
But what exactly is a limp mode, and how can you solve it? Read more to find out.
A Short Answer on How to Get a Truck Out of Limp Mode:
To get your truck out of limp mode, reset the switch by turning it off for around 30 seconds before turning it on again. If the warning lights disappear after switching on and the truck works fine, you are good to go. If it still frequently occurs, you can bypass it or get help from a mechanic.
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What Does it Mean When a Truck is Stuck in Limp Mode?
When a truck enters limp mode, the engine reduces its performance, limits the speed and RPM, and keeps the transmission from gear shifting.
When a limp mode happens, it usually is a sign that there is an error in the Engine Control Unit (ECU) or the Transmission Control Unit (TCU).
A limp mode is an “emergency mode” that indicates something wrong is happening in your truck’s mechanism. Thus, you should not just ignore it.
What Causes a Truck to Go Into Limp Mode?
A limp mode will occur when the ECU detects malfunctioning within its parameters.
The possible causes are brake malfunctions, engine issues, low levels of oil and coolant, transmission errors, and wiring issues.
Brake malfunctions happen when there is a leak in the hydraulic system or seized brakes.
Engine issues often occur when there are problems in the turbo system.
When your truck experience low levels in the oil or coolant system, it will also cause limp mode.
If your truck also has transmission errors, like if you find it hard to change gears, it can also cause limp mode to prevent your vehicle from further damage.
You also must frequently check the wiring since it is a prominent cause of erratic behaviors in trucks.
How to Get Freightliner Out of Limp Mode?
The general rule to get your truck out of limp mode is to detect the significant problem immediately.
In Freightliner trucks, some of the issues why it turns to limp mode are leaks in the EGR cooler, busted hose, and exhaust manifold.
A busted EGR flex pipe, broken motor, dead alternator, overheating sprinter, and broken motor mount are possible culprits.
Regardless of which issue you may detect, or if you already have some wild guess, you can confirm it by doing a test drive.
A test drive is more reliable, especially with no detected fault codes.
Start up the engine. If there is no check engine light, you can rev it. After the test drive, check under the hood to fix the part relevant to the issues of your truck.
Once you find out the problem, scan your truck to verify if everything is okay or if you have finally fixed the issue.
How to Get Hino Truck Out of Limp Mode?
First, you must shut the engine off to get a Hino truck out of limp mode.
Then, pull the cover on the right side of the dashboard, where you can find the fuses. Grab the fuse puller, which is the one with a white end.
Get the cover and turn it to the other side to see the fuse manual. You will see that the fuse you pull is for the engine ECU.
Pull the fuse again and plug it back in. After that, turn the truck on. You should see that your truck is finally out of limp mode. If not, you need to go to a mechanic.
How to Get an International Truck Out of Limp Mode?
If you want to get from limp mode to your International truck, ensure you are in a safe spot first.
Turn the engine off for about five minutes. You need to ensure that you will not disturb any other truck system for the time being. That way, the computer system can seamlessly disable the mechanism in the truck.
After five minutes, switch the truck on and try to shift gears. If it is successful, then your truck is out of limp mode.
However, if it is still in limp mode, you need to conduct a diagnostic scanner, battery disconnection, and inspect the automatic transmission fluid.
How to Get Peterbilt Out of Limp Mode?
When it comes to Peterbilt trucks, all the above steps are similar. However, when the issues persist, and you want to avoid costly mechanic repairs, here’s what you can do.
Turn the ignition on and plug an OBD port into the cab. It will automatically scan, detect, and delete error codes from the ECU of your Peterbilt truck.
If there are any deleted error codes, the truck will start to get out of limp mode and reset. After that, your truck is in full power now.
However, if the limp mode is still present, try to reset using a limp mode reset tool.
How to Get Kenworth Out of Limp Mode?
If you drive a Kenworth truck, all the above procedures to bypass a limp mode still apply to you. However, if the limp mode issue is getting more frequent, use a different method.
First, ensure you pull over your truck in a safe spot, especially if you encounter limp mode in the middle of the road and are far from any mechanic auto repair shops.
After you pull over, reset the computer of your truck. Then, check the fluids. If it is low, then it is the most probable cause of the limp mode. All you need to do is to top it up and check if it is still in limp mode afterward.
If that does not work, do the usual method of shutting off the engine and restarting it. Then, check the engine light if there are warning signs appear.
If there is, scanning the truck using an OBD/OBD2 scanner is the next solution before you finally decide to change any malfunctioning part.
How to Get Mack Truck Out of Limp Mode?
To get the Mack truck out of limp mode and the speed won’t go up, you need to twist the connector of the LHS oil pan.
This issue often occurs in Mack MP8 trucks. It will help if you get an up-to-date engine oil pressure (EOP) sensor.
If it is not the oil but the fuel that causes the limp mode, you can stalk the switch and pull the fuse connected to it. Then, follow the usual steps to deactivate the limp mode. Don’t forget to check the air dump as well.
How to Get the Volvo Truck Out of Limp Mode?
If you use a Volvo I-shift transmission on your Volvo truck, you can go directly to the Limp Home Mode right after you pull over your truck to a safe location.
The manual provides the instructions, but here’s an overview for your convenience.
If the transmission has a mechanical problem, press the L button on the gear selector. Then move the gear lever to the D position to activate the Limp Home Mode. After activating, you will see the “L” displayed as the driving mode in the DID.
With the Premium gear selector, the only available gears are the 1st, 3rd, and 5th forward start gears and the reverse gear R1. With the Basic gear selector, only 1st forward start gear and reverse gear R1 are available.
The truck operator cannot change gears in Limp Home Mode. Thus, it will deactivate when you turn off the ignition.
Is it Bad to Drive a Semi-truck in Limp Mode?
When something wrong happens with the engine or other parts of your semi-truck, it will turn into limp mode.
Your truck will then limit its features such as speed, HVAC system, and other extra features will deactivate for safety. Thus, it is problematic to drive in limp mode, so you may need to look for a safe space to pull over.
However, you can still drive your semi-truck in limp mode, depending on the alarming signs you get. If you continue driving, you may need to be extra cautious since it will be complicated to shift the gears, and it can get worse.