While transmissions are designed to be fairly robust, they can still develop mechanical or electrical problems from time to time. When the transmission warning light comes on, it normally means you should stop driving immediately to avoid major damage.
In this article, we’ll talk about what causes the transmission light to come on, if you can drive your car, and what you can do when your car’s transmission light is on.
What Is a Transmission Warning Light?
Much like a check engine light warns drivers of their vehicle’s engine potentially approaching trouble, a transmission warning light indicates that there’s a problem with your vehicle’s transmission. Which problem specifically is variable, and often make/model specific.
There are also a few known discrepancies in how the light may be indicated. Some vehicles depict a symbol resembling a gear with a thermometer, or a gear with an exclamation mark in some cases. Others may display a text prompt indicating a fault with the transmission.
What Can Cause the Transmission Light to Come On?
There exist a great many potential reasons for the illumination of a vehicle’s transmission light. Many of these reasons vary from one model of vehicle to the next.
It is a good idea for all motorists to familiarize themselves with the causes of this type of warning light.
#1. Lack of Transmission Fluid.
A lack of transmission fluid represents one of the more commonplace reasons for the illumination of a transmission warning light.
Remedying this situation requires topping off your vehicle’s transmission with lubricant and finding out the source of any leaks.
#2. High Transmission Temperatures.
Most vehicles also illuminate a transmission warning light in short order if the transmission begins to reach elevated temperatures.
In this case, it is important to assess the level and quality of your vehicle’s transmission fluid as a whole and change it per the manufacturer’s maintenance schedule.
#3. Logged Diagnostic Codes.
The vehicle’s transmission light may be illuminated in many cases if a transmission-specific fault code has been logged.
Sources of such codes can vary from simple electrical problems with the valve body to specific internal faults within the transmission itself.
#4. Maintenance Required.
In some cases, a vehicle’s transmission light may not indicate an actual issue at all. On the contrary, some vehicles utilize a similar light to indicate maintenance is due.
Can You Continue Driving With the Transmission Light On?
You should never drive a vehicle if its transmission light is on, since this condition may be symptomatic of one or more major transmission problems. Driving with a transmission light on can cause potential damage to the transmission, some of which may be severe.
If you are “stuck” behind the wheel with few other practical options, it is vital to check your vehicle’s transmission fluid level first.
Many transmissions have a dipstick located specially for this reason, allowing you to check its fluid content in seconds. Depending on the application, this fluid will need to be checked while in park or neutral.
In either case, the reason for the vehicle’s transmission light should be quickly diagnosed and repaired. This may save additional damage from being done to the transmission, some of which may be relatively expensive to fix.
If this is not something you would feel comfortable attempting, you should make an appointment with a trusted service center at the first possible opportunity.
Do All Cars Have a Transmission Light?
Not all manufacturers implement a transmission light. In fact, the majority did not start to include warning lights of this kind in vehicles until the last decade.
Transmission warning lights, unlike check engine, are a relatively new addition to the auto manufacturers. Therefore, if your vehicle is older than 10 years, it is relatively unlikely that a warning light of this nature is part of its specification.
In addition to a dedicated warning light, some models are developed with information of a similar purpose, which is scrolled across a car’s instrument cluster, in the event that a fault is to be logged concerning the transmission.
While some messages of this type are quite generic in context, others are far more descriptive.
How to Fix the Problem?
The following steps should be taken when troubleshooting the cause of a vehicle transmission warning light.
Likewise, one might refer to official factory service literature for their specific type of automobile when trying to work through complicated issues with the transmission.
#1. Pull Over and Assess the Situation.
If the transmission warning light suddenly comes on in your vehicle, find a safe place to pull over and check the warning. Refer to the care packaging for the included dipstick to check the fluid level in your transmission.
Topping off the vehicle transmission fluid is a good idea, but take care that you haven’t overfilled the fluid.
#2. Get Your Vehicle to a Safe Place.
Then, it’s time to decide if you will be having your vehicle towed or driving it home or to a preferred service facility.
If the rudimentary inspection has revealed leaks or if drivability issues have arisen, the vehicle should be towed to wherever it is to be repaired. Otherwise, take care to drive to your destination.
#3. Solve the Problem.
Now you must decide if you will be repairing the vehicle yourself or bringing it in somewhere for service. If you intend to select the latter option, pick a reliable shop with plenty of experience working on transmission issues.
Otherwise, you must have a good quality scan tool and factory-specific service manual in order to proceed.