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Posted On by Ralph
There are six main reasons why a key fob will not unlock doors. They break down into two categories: remote or lock problems. Once you figure out what type of issue you are experiencing, you can find the fix that will work for you.
When a key fob will not unlock doors, diagnosis and repair are often best left to a professional. But feel free to use the following information to attempt the work yourself. The information can only be general as each car and lock issue has almost limitless servicing permutations.
The most common reasons a car key fob will not unlock doors are:
When a car key fob will not unlock doors, it is either an issue with the fob or the door locks. Whichever is the source of your trouble must be replaced or repaired. Car key fobs often die and cause this issue, or the buttons can wear out just as the door locks themselves can wear.
The process of key fob replacement can be broken up into buying a new fob and programming your fob. Purchasing can be done online or at many department stores with automotive sections. Programming may require a locksmith or the dealership, both of which can also provide a new fob.
Test your spare key fob, and see if the issue persists. If you do not have a spare fob, use the electronic door lock switch on the driver side that locks and unlocks all doors. When remotes and interior switches are not working, you most likely need some form of car door lock repair.
You can get a new key fob when you have no spare, but you are unlikely to be able to program the device yourself. Most self-programming procedures require at least one working key fob. A locksmith or the dealership has tools to program keys directly to the car’s onboard computer.
If you have a physical key, this should still be able to operate your door lock. If the physical key is also not working, it is not that the car key fob will not unlock doors. You likely have a broken lock assembly. Contact a car lockout service if you cannot open a different door to gain entry.
The most obvious reason a car key fob will not unlock doors is that the remote is broken in some way. There is a chance the fob is damaged beyond repair. In those cases, you will need a brand new key fob. But to reduce your key fob replacement cost, we will discuss problems and solutions that do not require a new car key remote.
If a car key fob will not unlock doors or open them and has lost all functionality, then there is a chance the battery has died. If just the car key unlock button is not working or functionality is only limited, you may still be facing battery problems.
A dying battery can work intermittently or have too weak of a signal to work for certain distances. On the other hand, the cause of a key fob not working at all can be a dead battery. Diagnosis is only really possible with a signal reader or by changing the battery.
To avoid key fob replacement and troubleshoot the problem when a key fob will not unlock doors, a battery change is a good place to start. Even if it does not solve your problem, it is good to have a spare key fob battery on hand for future testing.
Open your car key fob with a flathead screwdriver or small pry tool. Check the battery number. Find a retailer who carries that battery. Most stores will carry various car key batteries in their auto parts or electronics section. Double-check that number before you make your purchase.
One of the hallmarks of worn buttons is the key fob working inconsistently. For example, when a key fob will not unlock doors unless you press the button several times or with extreme pressure, this is probably your issue.
You may also find that certain buttons work and not others. So your remote start button is not working, or the car key fob will not unlock doors, but it will lock them. This limited or mixed malfunctioning is one of the clearest signs of worn key fob buttons.
Visible damage or wear is a good indicator of this issue. In the most extreme cases, one or more buttons may have come off entirely. This damage does not necessarily require you to replace your car remote, though that is a simple solution.
Though it will be easier to get a new remote, it is cheaper to keep your existing circuit board and swap out the housing. As this video overview shows, all you need is the proper replacement housing, a small pry tool, and soldering equipment if you need to change the button contacts.
Deprogramming will closely mimic a dead key fob battery. Your fob will simply not work. But before you go and buy a smart key for your car, realize there are certain protocols on older vehicles that allow you to unpair an existing remote without accessing the onboard computer.
Some drivers accidentally perform these procedures by happening upon the correct sequence of button pushes and/or key turns. This sometimes happens when children are playing with the remote or the automatic locking buttons in the car.
The good news is that your car key programming cost can be as low as zero dollars. With self-programming methods so easy you can do them by accident, reprogramming the fob yourself should be simple. You just have to make sure this is your issue.
If you have deprogrammed your car key fob, you should have a similar re-pairing process you can do yourself. Check your owner manual or look online for your specific self-programming protocols. If you need any assistance, feel free to call an auto locksmith.
Sometimes when a car key fob will not unlock doors, it has nothing to do with a car remote not working. This type of issue may be the result of a failure with the door lock assembly or the vehicle’s electrical system.
A good indication of a door lock problem is when certain doors won’t unlock with a key fob, but others will. It does seem like multiple door locks will break roughly at the same time, but it is rare that all the door locks will go at once.
When the car door lock assembly is blocked, there will be no way to manipulate the door open. Even pulling on post locks or and using manual interior lock stitches will not work. This can cause a car door lock stuck in the locked position, so the key fob will not unlock doors.
Unlike problems native to the fob, when you have a blockage, the car door won’t open from inside or outside. Something unrelated to the lock assembly but still within the door may be preventing the lock hardware from moving.
Other than unrelated parts coming loose and clogging up the works, you could be dealing with rust. Many of the pieces in modern car door lock assemblies are plastic, but connection points may still use metal, which could be causing things to jam.
Use WD-40 in the crevices of all accessible locking mechanisms. If any moisture has accumulated and formed rust, it is likely to be through the built-in gaps in the door. If that does not work, remove the door cover and investigate the exposed assembly for any blockage.
Parts of the assembly can detach or break, so a key fob will not unlock doors even as it seems to control the door locks. It is often possible to hear your door lock assembly shift after a successful unlocking signal is sent from your fob. But in this case, the door will still not unlock.
You may still be able to pull or push interior lock actuators and feel no resistance with switches, but the door will still not unlock. Use every method of entry when your car key fob will not unlock doors, and see if all connections are still intact.
The cost to replace your car door lock will vary depending on the extent of the damage. You will likely need partial replacement of parts. In some cases, this can require the purchase of the full lock assembly, but it could be as simple as snapping a part back in or replacing a screw.
Not every discontent requires replacement. Sometimes you can weld, glue, or otherwise reconnect what has broken. Most times, some small part will need to be replaced, which is not widely available without replacing a car door lock cylinder or larger part of the assembly.
Issues with your vehicle’s electrical system will often present as more than just a car key not working. The wiring in a car is usually bundled, so damage is likely to cause several seemingly unrelated issues. Perhaps your key fob will not unlock doors, but your horn also isn’t working.
Any trouble with your wiring should not affect the manual manipulation of your car door lock. Using a physical key or moving a post lock should work even if the key fob will not unlock doors. If only the electronic opening procedures are failing, this is a strong indication of a wiring issue.
The electronics may not be damaged. Sometimes a mechanic or other technician will accidentally disconnect a wire while reassembling the panels on a door or dashboard. If you recently disassembled to fix car door latches or a car key replacement that required access to the onboard computer, this may have happened.
Test for a charge at the connection point between your lock actuator and your electrical system. If you do not find a current and there is no visible sign of disconnection or fraying, follow the wire until you find the problem. You may need to patch or replace the connection.
Before you ask, “where can I get a key made,” determine whether or not your issue stems from the remote. When a car key fob will not unlock doors, the problem could be with the door. But regardless of the cause, you may not need a new key fob.
You can use the methods described above to fix your issue yourself or contact a professional locksmith. When in doubt, see if United Locksmith services your area. And drop a comment below if you have any further questions.