Your dashboard display has a number of lights that will come on to alert you to problems. Most drivers are familiar with the check engine light which can be illuminated for literally thousands of different reasons to indicate a problem somewhere under the hood of your car. The battery light often comes on the moment you first turn your car on, it will also come on to let you know that you have a problem with your power in the vehicle. But the transmission light is another warning light that you need to be aware of and pay attention to when it does come on. It's much rarer than a battery light or the check engine light, but it's extremely important and one you never want to ignore.
Not every vehicle has a transmission light, older vehicles especially didn't actually include one of these. Once upon a time if you were having serious transmission problems, they could potentially come at you almost out of nowhere. If your transmission overheated while you were on a long road trip, you’d notice it because your transmission died on you. These days, most cars include the transmission light to let you know you have a problem which will hopefully alert you to it before it gets so bad your car stops working. In fact, most cars produced since 2012 included these warning lights as an advance warning system.
Not every vehicle uses a specific transmission warning light to alert you to a problem with your transmission. By that we mean there isn't a dedicated transmission light in every vehicle. If you have a problem with your transmission, it's possible that a different light that already exists will come on and cover this area as well. It may be something like a traction control light, a service engine light, or an overdrive warning. It's really hard to say without knowing the exact make, model, and year of your vehicle. However, if you check your owner's manual it should tell you what kind of warning you need to be on the lookout for when you have a transmission issue. At the very least you should be able to Google the make and model of your vehicle and find out for sure what to look for.
It's also worth noting that for some makes and models of vehicles the transmission light isn't always a warning of a problem, rather an alert for maintenance. Most vehicle manufacturers will include a list of scheduled maintenance in the manual that you should be following. For instance, your transmission fluid may need to be checked every 100,000 miles or so. If that's the case, the warning light on your dashboard may come on not because you have a specific problem with your transmission but because it's time to get the fluid level checked. Again, check your manual to be sure because it should let you know what you're on the lookout for.
If your transmission light came on specifically because you have a problem with your transmission, there may be other signs and symptoms you can be able to look at to confirm for you that there is an issue that's going to need to be addressed.
What Are the Signs and Symptoms Your Transmission is Going Out?
Transmission problems can manifest in many different ways. If you experience one or more of these symptoms along with that transmission light going off on your dashboard, you may want to consider heading into a mechanic as soon as you can to get the problem looked at.
Transmission problems have an uncanny way of going from bad to worse pretty quickly. If you're experiencing these, you don't want to wait too long because the cost of getting transmission repairs if it fails completely can stretch well into the many thousands of dollars.
Burning Smell: When your transmission overheats you may start noticing a burning smell in the cabin of your vehicle. This is a result of transmission fluid that has become so old or contaminated it's no longer able to do its job properly. The smell will be acrid and burnt and a bit oily.
Inability to Shift: Obviously if there's a problem with your transmission then your transmission is not going to be able to do its job properly. That means you're going to have trouble shifting from one gear to another. Whether your transmission fluid is too old and contaminated or you have a leak and there's not enough in the system you'll find that shifting between gears, trying to get into reverse or park is going to be a struggle and it may not work at all.
Slipping Gears: Different from a problem with shifting gears, when your transmission slips between gears that means you're changing gears even when you don't want to. This often happens from a higher gear slipping into a lower gear. This could be extremely dangerous if it's happening while you're out driving, especially if your vehicle slips into neutral or even park somehow.
Noises in Neutral: If you have your vehicle in neutral but you're noticing sounds coming from your transmission then that's a definite sign of a problem. Your car shouldn't be making any particular noises when it is in neutral but if it's making any kind of grinding, knocking, clunking sounds then you may have either bad transmission fluid or there could be a mechanical issue at play.
Grinding Noises: This is one of the most common signs of a problem with the transmission, particularly in automatic transmission, when it starts growling when the gears change in a very noticeable and loud way. This may also be accompanied by shaking in the vehicle.
Humming Noises: If you're noticing a humming sound while you're driving, possibly a whining noise and even some kinds of clunking sounds that could also be a mechanical issue with your transmission.
Fluid Leaks: Typically, transmission fluid is red in colour and very noticeable if it's puddling in your driveway. Sometimes a transmission leak can be very small though so you may only get a drop or two underneath your vehicle. It's somewhat sweet smelling like antifreeze, but the color should be a dead giveaway. If your transmission fluid is bad it will be a thicker, muddy colour.
Can a Check Engine Light Indicate Transmission Problems?
As we said, not every vehicle uses a transmission light to indicate an issue. Sometimes your check engine light will be illuminated to alert you of a problem with your transmission. Unfortunately, because there are so many potential causes for a check engine light to come on the dashboard it may not be apparent right away that transmission is the issue. And even though you obviously should get your car checked when the engine light comes on, as drivers we do sometimes let this one slide. There are a number of reasons for a check engine light to come on that will not affect the operation of your vehicle right away, so many drivers are willing to ignore it and continue driving with this on.
One way to be able to easily narrow down why the check engine light came on without actually having to go into a mechanic is to invest in your own OBD2 scanner. An on-board diagnostic tool is what a mechanic will use to diagnose the warning lights that pop up on your dashboard as well. When you plug one of these in your car it is able to give you a readout of the nature of the problem that caused the light to come on to begin with. This is very helpful to check an engine light because it can direct you to the exact part of your vehicle that's causing a problem, which in this case means your transmission.
You can get an OBD2 scanner for a pretty reasonable price on sites like Amazon.com. The one your mechanic uses maybe several hundred dollars, but you can get a decent quality one that will tell you what's going on with your vehicle for around $30. It doesn't fix the problem in any way but it does let you know if what you're dealing with is transmission, the alternator, your catalytic converter, or any other number of issues that may pop up under the hood. That way you're better able to assess just how quickly you need to get to the mechanic to have this issue addressed. And if it is your transmission, you want to make sure you get it looked at pretty soon
What Does a Blinking Transmission Light Mean?
When your transmission light is off then you have nothing to worry about and things are working normally. When a transmission light comes on then that's typically a sign that you need to be aware of a problem with your transmission and you should take it in to get serviced by a mechanic. However, there are also some instances where the transmission light may flash off and on which can be extremely confusing since that's not necessarily a typical kind of warning.
If your transmission light is flashing, it's usually related to an issue with your transmission overheating. This can happen for any number of reasons but mostly it's because you run low on transmission fluid, it's unable to keep your transmission operating at the right temperature as a result, and it starts to overheat.
Is it Safe to Drive with a Transmission Light On?
If your transmission light came on to warn you that you have a problem with your transmission temperature related to your fluid levels being low, then driving in this condition is a bad idea. It’s very likely that you can continue to drive for a while like this, but you need to know that the longer you continue to do so the worse the problem is going to get. Arguably the temperature is going to continue to rise as you continue to either leak fluid or run contaminated fluid in your transmission. It's going to continue to leak out or break down and the transmission will eventually seize up on you.
If your transmission fails and you need to rebuild or replace it, you could be looking at a repair bill that's around $1,500 to $3,500. This is a significant part of your vehicle and one you need to do your best to maintain.
When your transmission light comes on the best thing you can do is stop driving as soon as you can. This warning light means that your transmission is in imminent danger right now. As soon as you're able to do so you should find a place to stop the vehicle and let it sit until your transmission is able to cool down. Once your transmission has cooled down you can attempt to start the vehicle again and continue to drive but make sure you're doing so carefully. Your goal at this point should be to get to a mechanic and nothing else. If the light comes back on, stop again and let it cool down. If you're too far from a town or a mechanic that you may need to call for a tow at this point.
The Bottom Line
When your transmission starts to fail it doesn't give you a lot of time to react. If your transmission light comes on this isn't the kind of thing you can brush aside and worry about when the weekend rolls around or whenever you have the time to deal with it. If it's a problem right now, you're going to need to worry about it right now. The longer you let it go, and that could just be a matter of miles down the road, the more likely you are to suffer a severe and expensive failure to your transmission system. You never want to take a chance with something like this and end up with a massive repair bill and a lot of headaches.
When your transmission light comes on, head to a mechanic as soon as you can to get it looked at.