Key fobs are a wonderful convenience, but they can cause headaches when they stop working. You’ll want to get your key fob working again as soon as possible, so we’ve compiled the top problems affecting fobs and how you can fix them.
A key fob can stop working for a couple of reasons:
- Low battery - Try replacing the battery before any other step.
- It needs to be reset or reprogrammed - Consult your owner’s manual on how to reprogram your fob.
- Wear-and-tear - Open up the fob and check the mechanical pieces and wiring inside to see if there are any breaks or debris.
The make, model, and type of key you own will change the steps since many manufacturers like to personalize the way fobs are made and programmed. In this guide, we’ll go more in-depth into how to fix each potential problem below as well as how to unlock your car if the fob isn’t working. Just keep reading!
Steps To Fix A Wayward Key Fob
Remember to consult your owner’s manual first to get a grasp on whether these specific steps will work with your model or key fob before you begin. Reading it at the beginning will save a lot of time and effort during the whole process.
How Do You Check If A Key Fob Is Working?
Some fobs include a small LED that lights up when you push a button, which is very convenient. If your fob doesn’t have that feature and it’s still not getting a response, try putting a new battery in and reprograming it. If that doesn’t work, then it’s likely your fob is either broken or something is wrong with your car’s signal receiver.
A key fob may not be working for a reason as simple as having a low battery. Before you move on to any other step, replace the battery to see if that solves the issue.
How To Replace The Battery
Your fob will either have a small slider, switch, or a small gap that you can use to pry it open to get to the battery. Take note of what type of battery is already in there and which way it’s facing (they’ll usually be the disc-shaped batteries) so you know what kind you’ll need. Some disc-shaped batteries provide similar voltage but are slightly different sizes.
Double-check your manual and see what other people say on the internet before trying out different types of batteries. When you put the new one in, make sure it’s facing the correct way. Put the cover back on and test it to see if that fixed the problem.
Reset Or Reprogram The Key Fob
Sometimes you will need to reset your key fob after you replace the batteries. If that’s the case, here’s a quick step-by-step guide for how to reset it:
- Consult your owner’s manual. Some manufacturers and models require slightly modified steps to properly reprogram the fob, so it’s best to check the manual for instructions first.
- Find the driver’s side door lock. The lock can be hidden under a small cap next to the door handle. There’s usually a small gap to insert your key or a screwdriver to pop it open.
- Unlock the door with your metal key. After this, the steps usually begin to differ depending on the model and manufacturer. Almost all of them require inserting the key into the outside lock at some point.
- Insert the key with the fob into the lock or ignition and follow the instructions in the manual.
In the video below, this gentleman inserts his key into his Volkswagon and starts the engine within a minute of pressing the unlock button on the fob and opening his locked door:
If you own a keyless entry-and-start fob, then the dealership will have to reprogram it. Those fobs often feature a rolling-code, which means that the code sent between the car and the fob changes every time they’re used in order to deter car thieves. A rolling-code adds security, but it makes DIY reprogramming a lot more complicated if not impossible.
You can also check out our list of How To Prevent Car Break-Ins for maximum security and some peace of mind.
What Is The Cost Of Reprogramming A Key Fob?
The cost of reprogramming a key fob depends on what type of fob it is and who you’re talking to. Some dealerships and locksmiths will program a key free of charge, but others might bill you for the cost of labor. If they charge for it, you might be looking at a bill of $50-$100 or more.
Usually, you can DIY instead and save a couple of extra bucks. You can find instructions to program a fob in your owner’s manual. And if you don’t have the physical version, you can always look it up online.
Wear And Tear
Cleaning your fob and checking the mechanical parts for wear is a lot simpler than you might think. We only recommend trying this step for fobs that are not keyless entry-and-start remotes; they are made differently and can cost hundreds of dollars if you make a mistake. Here are some easy to follow steps:
- Open the fob by looking for a small gap in the seam to insert a screwdriver and pry it open. Some fobs might have a screw keeping the two halves together, so you might have to unscrew that first to get inside.
- Use canned air to spray the inside. Remove the battery and set it aside. You can take this opportunity to replace the battery once you put everything back together. But for now, it can’t be in the fob.
- Remove the button pad from the remote and rub alcohol with cotton swabs around the buttons and frame to clean it. Let it dry before putting the fob back together.
- Remove the circuit board. After repeated use, the contacts between the circuits can wear down and not touch for proper currents to pass through. The contacts are usually colored gold. Clean them with more alcohol and swabs. Let them dry, then reassemble the whole thing and test it out.
- If that doesn’t work, you might have to build up or reapply the contact spots. You can use tiny amounts of metallic paint or conductive coating solution to reconnect the contacts. Be warned: they should only touch the contact points and nothing else, or they could ruin the circuit board. Let it dry for at least 12 hours before putting the fob together again.
If none of these steps worked, call your local car dealership and ask if there are any other potential issues. You can buy aftermarket key fobs, too. Not all aftermarket car fobs work with every model, so check that first.
How Do You Unlock Your Car When The Key Fob Dies?
If you have a metal key for that car, you can use it to manually lock or unlock your car. The physical lock will be in plain sight on some older models, but for others, they might be hidden. If you don’t see a lock on the driver’s door, check the plastic molding next to the handle. You can pop it off using a screwdriver or other thin, sturdy tool if it doesn’t come off easily. The lock should be underneath.
To save some headaches and time, prepare a backup metal key and fob at a locksmith. They're a cheaper alternative that lets you into your car if you lose your main key. For more guidance, check out our article Where To Get Car Keys Made?
If you have a keyless entry-and-start system, you’re still covered. Most manufacturers have an over-the-air emergency service that can unlock and start your car remotely via an app or phone call. Others offer roadside assistance. Some models even have an emergency key hidden inside the fob that you can use. Consult your owner’s manual to see which options you have while you’re out and about.
Now that we’ve gone over the prominent issues with car fobs and how to fix them, you can rest easy. You now know how to replace the battery, reprogram, clean, and fix it. The open road is yours once again.
If you run into any other problems, like Your Car Won’t Start But The Radio And Lights Turn On, we have guides for those too!