A limp what? A "limp transmission" refers to a transmission that is running in "limp mode." Limp mode, most often referred to as fail code mode, is when the computer in the car finds a problem. Basically, if the computer is expecting certain specifications and something happens outside of its programming, it enters fail code mode. Continue reading to learn more about what causes limp mode and actions you can take.

What Causes Limp Mode?

Limp mode can be caused by a variety of sensors on your car. The car's computer is programmed to certain parameters for each of these sensors and when one of them sends information that the computer doesn't recognize as normal, the computer reacts by activating emergency measures programmed by the manufacturer.

What Occurs During Limp Mode?

When the computer switches into limp mode, it activates a secondary programming option that is designed to prevent further damage to your transmission. The throttle position sensor, the manifold absolute pressure, and the speed of the vehicle are the main sensors that involve the transmission.

Once the computer enters limp mode, the specific actions that occur afterwards depend on what the manufacturer programmed the car to do. Generally, you can expect a series of actions that will leave your speed limited and allow your car to get home or to a service station instead of leaving you trapped on the side of the road.

When the signals indicate a mechanical failure, the computer will switch into emergency mode. The transmission is disabled from shifting gears and allows only second or third gear. The transmission fluid's pressure is set to high to protect the transmission's internal parts and the signals are activated to high so the clutch doesn't slip. Your car is now limited to slower speeds and stuck in a single gear.

What Can You Do When Your Car Enters Limp Mode?

• Remember that limp mode is designed to protect your vehicle, so don't panic.
• Immediately drive to a service station if there is one nearby.
• If you there is no service station nearby, have your car towed. You can either drive home and order a tow, or be towed from the side of the road.
• Do not drive your vehicle in limp mode (other than to get it serviced) because more damage will be done.

Remember that limp mode is to protect your vehicle from further damage and give you a way to get home or to a service station so you aren't stranded dangerously on the side of the road. Realizing what limp mode is and what to do about it will help you from causing irreparable damage to your car. 

To learn more about auto transmissions, visit a company like A Transmissions.