The system
What kind of key does a Forester use?
The Forester has been sold in the United States since the late 1990s, and in that time its key has gone through almost every stage a modern car key can go through. The earliest cars used a plain metal key with a separate keyless entry remote, and some of those early cars may not have an electronic immobilizer at all. Later Foresters added a transponder chip inside the plastic head of the key, which the car reads before it lets the engine run. After that came the integrated key, where the lock and unlock buttons live in the same head as the chip. Finally, Subaru offered Keyless Access with push-button start, first on upper trims and then on a much wider share of the lineup.
That history matters because two Foresters parked side by side in the same lot can need completely different work. One may need a blade cut and a chip registered to the car. The other may need a proximity fob that talks to antennas in the doors and cabin and never goes into a cylinder at all, except for the small emergency blade tucked inside it. The badge on the tailgate does not tell you which one you have. The year helps, the trim helps more, and the key itself, if any key survives, settles it.
A quick way to sort it out at home: if your Forester has a round Start/Stop button on the dash, it uses a Keyless Access fob. If you turn a key in a cylinder on the steering column, it uses a blade key, and then the question is whether the buttons are part of the key head or on a separate fob hanging from the ring. If you have a separate fob, there is usually a small transponder in the plastic key head as well, and both pieces have to be accounted for.
Subaru key blades are cut with a conventional edge profile on many older cars and with a different profile on some later ones. We match the blade to the lock cylinder the car actually has, not to a chart, because Foresters that have had a door lock or ignition replaced over the years can carry a cylinder that no longer matches the original key code. That is not rare on a vehicle this age, and it is the reason we test the finished blade in the door and the ignition before we call anything done.
None of this requires the car to be towed anywhere. For the generations we support, the blade is cut at the vehicle and the electronics are registered through the diagnostic port with the car sitting in your driveway, your work lot, or wherever it stopped.
Systems by generation
How the Forester key changed from one generation to the next
The ranges below are general. Subaru did not change every trim at the same moment, and a car built late in a model year can differ from one built early. Treat the table as a starting point, then confirm from the car or the key you still have.
| Generation, roughly | What most owners carry | What the job usually involves |
|---|---|---|
| Late 1990s to early 2000s | Metal key, often with a separate remote fob | Some cars have no immobilizer. Cutting may be the whole job, plus remote pairing if the fob is lost |
| Mid 2000s to around 2008 | Transponder key with a separate remote on many cars | Blade cut plus chip registration. The remote is paired as its own step |
| Around 2009 to 2013 | Transponder key, with integrated remote heads appearing on later cars | Registration through the diagnostic port. Remote functions checked separately from starting |
| Around 2014 to 2018 | Integrated remote key on many trims, Keyless Access on upper trims | Either a remote head key or a proximity fob, decided by the ignition style |
| 2019 and newer | Keyless Access fob on most trims, blade key on some base models | Proximity fob registration, emergency blade cut to the door, full function test |
The older end of the chart is the simplest in one sense and the most unpredictable in another. A Forester from around the turn of the century may start on a plain cut key, which means a new blade cut to the right code is all it needs to run. But those cars are old enough that the separate remote has often been lost, replaced with a used one from a salvage yard, or simply abandoned. If you want remote locking back, say so, because pairing a remote is a different step from cutting a key, and a used remote may or may not be accepted.
Once the transponder arrives, the job becomes two jobs in one visit. The blade has to turn the cylinder, and the chip has to be registered in the car's immobilizer memory. A key that only has the first half will open the door and turn the ignition, and then the engine will crank and quit or refuse to crank at all, depending on how the system reacts. That is the most common complaint we hear from Forester owners who had a copy made at a hardware counter without the chip being handled properly.
The middle generations are where the integrated key shows up. On these, the chip and the remote share a head, so a cracked case or a dead remote does not always mean the key is electronically dead. We check the chip and the remote separately. It is possible for the car to start on a key whose buttons have stopped working, and the fix for that is different from replacing a key that the immobilizer no longer recognizes.
Keyless Access Foresters work differently. The fob stays in a pocket or bag, the car detects it through antennas, and the engine starts with the button. If the fob battery is weak, most of these cars have a backup method where the fob is held close to the start button so the car can read it at very short range. The owner's manual for your year describes the exact method. If that backup works, the fob is still registered and the problem is probably the battery. If it does not work with a known good fob either, the issue may be on the car side, and we test that before selling anyone a new fob.
Getting a Forester ready for the visit
Find the year and trim on the registration or the door jamb sticker. Look at the dash and note whether there is a Start/Stop button. Gather every key and fob you can find, including the one in a kitchen drawer that you are not sure about, because registration work on many systems touches every key at once. If a key no longer works, bring it anyway. A dead key can still tell us which blade and which electronics the car expects, and on a Forester of uncertain history that saves time.
Diagnosis
What usually goes wrong with Forester keys
Worn blades are the first thing we see on older Foresters. A key that has been used every day for ten or fifteen years loses the sharp edges on its cuts. It still turns, but only if you jiggle it, lift it, or pull it slightly out of the cylinder. Copying that worn key onto a new blank just reproduces the wear. We cut to the original code where it can be recovered, which gives a key that behaves the way the lock was designed to work.
Cracked key heads are the second. The plastic around the ring hole breaks, the head splits along its seam, or the blade works loose from the head. On a transponder key, the chip is often still fine inside. If the case is replaced carefully, the same chip can move into the new shell and the key keeps working without reprogramming. If the chip falls out and is lost on a parking lot, that key becomes a new key job.
Remotes that stop reaching the car are usually battery problems, but not always. Button pads wear through, contacts corrode after a key goes through a washing machine, and the circuit board can crack if the fob is dropped on concrete often enough. We test the remote output before assuming a battery will fix it.
An immobilizer light that flashes or stays on when you try to start is the car telling you it did not accept the key. That can mean the chip is damaged, the key was never registered, the key was registered to another car, or there is a fault in the reader ring around the ignition. Trying a second known key tells you which side the problem is on. If both keys fail the same way, the key is probably not the cause.
A weak or failing vehicle battery can also cause confusing symptoms. Low voltage can interrupt communication between the key and the car and make a perfectly good key look bad. If the car has been sitting in a driveway in January, it is worth checking the battery before blaming the key.
Delaware use
Where Foresters end up needing keys around here
The Forester is a practical, all-weather wagon-shaped SUV, and in New Castle and Kent counties it gets used that way. It carries kayaks down to the beaches, dogs to the parks, and kids to practice fields. It gets parked at trailheads in the White Clay Creek area, at the Brandywine parks near Wilmington, and at farm stands along the back roads south of Middletown. A lot of lost Forester keys disappear exactly where you would expect: dropped in tall grass, left on a bumper while loading gear, or zipped into a jacket that then went into somebody else's car.
It is also a common family hand-down. Parents in Hockessin or Pike Creek pass an older Forester to a student heading to Newark, and the spare key stays in the parents' house while the car goes to campus. When the one key on campus gets lost, the car is sitting in a lot near the university and the only other key is miles away. That is a solvable situation, but it helps to know early whether the spare actually exists, because it changes whether the job is a simple duplicate or an all keys lost job.
Further south, Foresters around Dover, Smyrna, Camden and Milford are often commuter cars that also handle farm lanes and gravel. Keys in those cars live hard lives: dust, moisture, and a lot of being dropped. We see more worn blades and cracked heads from those areas than lost keys, and many of those are repair jobs rather than full replacements.
Wherever the Forester is, the practical requirements are the same. We need to reach the driver's side door and the diagnostic port under the dash, which means the car cannot be boxed in tight against a wall on the driver's side. Parking garages with low clearance are usually fine because nothing about the job needs height. If the car is in a gated lot or a secured garage, have the access code or a way to let us in.
How it works
What happens when we make a Forester key
The first step is ownership. Before any key is cut or programmed, we look at the registration or title and a photo ID that matches it. If the car belongs to a parent, a spouse, or an employer, we need to see how the person asking for the key connects to the vehicle. That step protects you as much as anyone, because a key made for the wrong person is a stolen car waiting to happen.
The second step is identification. We confirm the generation, the ignition style, and which electronics the car expects. If an original key exists, we read it. If no key exists, we identify from the vehicle.
The third step is the blade. For an existing key in good condition, we can often cut from that key. For a worn key or no key, we work from the lock itself or from code information, so the new blade is cut to how the lock was built rather than how the old key has worn.
The fourth step is registration. For transponder keys and Keyless Access fobs, the new credential is added to the car through the diagnostic port. On some systems, adding a key requires every key you intend to keep to be present, because the registration process rewrites the list of accepted keys. Any key that is not present at that moment can stop working afterward. We explain which case applies before we begin.
The last step is testing, and we do it thoroughly. The blade has to turn the door lock and the ignition, if there is one, without force. The engine has to start and keep running several times. The remote buttons have to lock, unlock, and open the rear hatch where the car supports that. On Keyless Access cars, the doors have to respond to the handle sensors and the button has to start the car with the fob in a pocket. Every key you are keeping gets the same test.
Two routes
Locksmith or Subaru dealer for a Forester key?
A dealer can supply original Subaru hardware and has factory software for every system the car might use. If your Forester has had a security module replaced, has an unresolved electrical fault, or is new enough that field tools do not yet support it, the dealer is the right place and we will say so.
The trade-off is that most dealers need the car in their service bay. If every key is lost, that usually means a tow, and then a wait for a key that may have to be ordered by code. For a Forester that is otherwise healthy, that is a lot of effort for a job that can often be finished in your driveway.
We can supply original equipment keys or quality aftermarket keys depending on what the car and your budget call for, and we will tell you which one you are getting before we cut it. An aftermarket key that matches the electronics and blade properly is a sensible choice for a spare. For a daily key on an upper trim Forester with Keyless Access, some owners prefer the original part for the fit and button feel, and that is a reasonable choice as well.
If you still have one working key, the easiest and most useful thing you can do is have a second one made now, before the first one gets lost. An all keys lost job is always more involved than a duplicate, and a Forester with a single key is one dropped ring away from that situation.
Straight answers
Subaru Forester key replacement FAQ
Can you make a Forester key if every key is lost?
In many cases, yes. We confirm ownership, identify the generation and ignition type, cut a blade to the lock, and register a new key or Keyless Access fob to the car through the diagnostic port. The car does not normally need to be towed. If the Forester has had its security module replaced or has a network fault that stops the car from communicating, the job may need to go to a Subaru dealer, and we will tell you that after testing rather than guessing.
My copied Forester key opens the door but the engine will not start. Why?
The blade is fine, but the car has not accepted the electronics. Most Foresters from the mid 2000s onward need a registered transponder chip in addition to a correctly cut blade. A copy without a chip, or with a chip that was never registered to your car, will turn the lock and then fail the immobilizer check. Watch for a security light on the dash. Filing the blade will not help. The fix is a properly matched key registered to the vehicle.
How do I start my Forester with a dead Keyless Access fob?
Most Keyless Access Foresters have a backup method where you hold the fob against or very close to the push start button so the car can read it at short range. Your owner's manual shows the exact method for your year. If the car starts that way, the fob is still registered and a new battery is likely the cure. If it will not start that way with a second known fob either, the problem is probably on the car side and needs testing.
Can a cracked Forester key head be fixed instead of replaced?
Often it can. If the chip and the remote circuit are undamaged, they can move into a new shell with a new blade cut to match your lock. The key then keeps working without reprogramming. This is not a good idea if the board has corrosion from water or the chip is already lost. In those cases a new key is the better choice. We test the old parts before recommending either route.
Should I remove a lost Forester key from the car's memory?
If the key was lost somewhere connected to the car, such as a parking lot where it sits every day or on a ring with your address, removing it is worth considering. Deleting a lost key from the immobilizer means it can no longer start the engine. Remember that the blade on that lost key can still open the door lock mechanically, because erasing electronics does not change the cut of the lock. All keys you keep must be present when the memory is changed.
Is an aftermarket Forester key a good idea?
A properly matched aftermarket key can work very well, especially as a spare. It has to match the blade profile, the chip or proximity electronics, and the button layout for your year and trim. Very cheap keys bought online sometimes have the wrong electronics or poor cases that split quickly. We tell you which category of key you are getting before we cut it, and we test every function at the car before we leave.
When does a Forester need to go to the dealer instead?
When the car has had its immobilizer or body control module replaced, when there is a network or electrical fault that stops the car from communicating, when a Subaru service action controls key registration, or when the car is too new for the tools available outside the dealer. Outside those situations, most Forester keys can be made at the vehicle. We diagnose the car before selling you a key, so you are not paying for a key that the car cannot accept.
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