As of October 2026, a spare key that starts the car and opens the driver's door but will not open the trunk or glove box is most often a valet key working as designed, not a faulty key. The other causes are a copy made from a valet key, a trunk lock-out switch left on, a rarely used lock that has seized, and a lock that was replaced and never matched. If you need a full master key made, the published Fort Worth bands are $130 – $220 for a transponder key and $160 – $260 for a remote head key. Call or text 817-674-2304 with the year and model.
The Short Diagnostic Table
| What you see | Most likely cause | What to do |
|---|---|---|
| Key head is grey, or a different colour from the main key | It is a valet key | Nothing is wrong. Use the master, or have one made |
| Key head is black, but it was copied from the spare | Copy of a valet key | Have a master cut to the factory code |
| Master key will not open the trunk either, and the inside release is dead | Trunk lock-out switch is on | Find the switch, usually in the glove box |
| Key enters the trunk lock and will not turn | Seized lock from disuse | Lock service, not a new key |
| Key will not enter, or turns freely and nothing happens | Lock replaced, damaged or disconnected | Lock repair or rekey, quoted per vehicle |
Find your row before spending anything. Three of the five need no new key at all.
What a Valet Key Is
For decades, many manufacturers supplied two kinds of key with a new car. The master key did everything: doors, ignition, trunk and glove box. The valet key did less. It would open the driver's door and start the engine, and it was deliberately unable to open the trunk or the glove box.
The idea is in the name. You hand the valet key to a parking attendant, a body shop or a service desk, and whatever you locked in the trunk and glove box stays locked.
The limitation is mechanical. A valet key has a slightly different blade from the master, so it lifts the wafers in the door and ignition but not the extra ones fitted to the trunk and glove box locks. It is not a setting and it cannot be switched off.
Honda, Acura, Toyota and Lexus all supplied valet keys widely, and the common tell is the colour of the plastic head: the master is black and the valet is grey. Other makes used a different shape or stamped the head. If your car came with a small tag or a third key in the owner's wallet, that was probably it.
Why So Many People Only Have the Valet Key
Because cars change hands, and keys do not always follow.
The master key is the one that gets used daily, so it is the one that gets lost. The valet key sat in a drawer. When the car is sold, traded or passed to a family member, the key in the drawer becomes the only key.
The new owner drives the car for months without a problem. Then they need the spare tyre, or something is locked in the glove box, and the key that has always worked suddenly does not. Nothing changed. That key never could.
It is a familiar call on older Hondas, Acuras, Toyotas and Lexus models, and the good news is that the car is fine.
Cause Two: A Copy of a Valet Key
A duplicate inherits the limits of whatever it was copied from. If the hardware store traced a valet key onto a black-headed blank, you now own a valet key that looks like a master.
This one fools people, because the colour test passes. The giveaway is the history. If every key you own was duplicated from one original, and that original was the grey one, none of them will open the trunk.
The fix is not another copy. It is a key cut to the factory code, which produces the master blade from the vehicle's own specification.
Cause Three: The Trunk Lock-Out Switch
Many sedans have a second half of the valet system: a switch that disables the trunk release inside the cabin. On a number of Honda, Acura and Nissan sedans it is inside the glove box. Switch it off, lock the glove box with the master key, hand over the valet key, and the attendant cannot reach the trunk by any route.
If that switch gets bumped, the interior trunk release and sometimes the remote trunk button stop working. It looks like a failure. It is a switch.
So if your master key is the one that will not open the trunk, or the release lever by the driver's seat does nothing, open the glove box and look for a small switch near the top or side before assuming anything is broken. Your owner's manual shows where it is.
Cause Four: The Trunk Lock Has Seized
The trunk lock on a modern car is used almost never. People use the remote button or the release in the cabin. The key cylinder on the lid can go ten years without a key in it.
Locks that are not used collect dust and lose their lubrication. In a Fort Worth summer, heat does the rest. The first time someone needs the mechanical lock, usually because the car's battery is dead and the electric release is not working, the cylinder will not turn.
The signs are different from a valet key. The correct master key goes in fully and then binds. It may turn a few degrees and stop.
Do not force it. A key twisted hard in a stuck lock snaps, and then there are two problems. If that has already happened, see broken key extraction. A seized cylinder is serviced or replaced, and it is a lock job rather than a key job.
Cause Five: The Lock Was Replaced and Never Matched
After a rear-end collision, a trunk lid or its lock is often replaced. If the replacement lock was not rekeyed to the car, it came with its own key, and that key may have been lost years ago.
The same happens to glove boxes. A broken latch gets a replacement from a salvage yard, with a lock coded to a different car.
The sign here is that the master key, which opens the doors and runs the ignition, will not turn in one particular lock, and that lock looks newer or slightly different from the rest. The fix is to rekey that lock to match the car. It is quoted per vehicle.
What About Smart Fobs?
Push-button cars moved the valet function rather than removing it.
The fob contains a slide-out emergency blade. That blade is the mechanical master: it locks the glove box and, on many sedans, the trunk pass-through or lock-out. To use valet mode, you lock those, remove the blade, and hand over the fob without it. Many newer vehicles add a valet setting in the infotainment system that locks the trunk and hides personal data behind a code.
So on a push-button car, "the spare will not open the glove box" usually means the spare fob is missing its blade, or the blade in it was never cut. An uncut emergency blade is common on replacement fobs. It is worth checking today rather than on the day the fob battery dies. We cover that risk in the car locked itself with the keys inside.
The Five-Minute Check
- Look at the key head. Grey, or visibly different from another key for the same car, means valet.
- Ask where the key came from. Supplied with the car, or copied from another key?
- Try every key you own in the trunk lock and the glove box.
- Open the glove box and look for a trunk switch. Check the owner's manual.
- Feel the lock. Does the key stop partway in, go in and bind, or turn freely with no result? Each means something different.
- Check the car's battery. If the electric trunk release is dead too, low voltage may be the real problem.
If step one says valet key, you have your answer. The remaining question is whether you want a master.
Three Things Not to Do
Do not have the key copied again. If the key in your hand is a valet key, a fourth copy will behave exactly like the first three.
Do not force the key in the trunk or glove box lock. A valet blade is being stopped by wafers it was never cut to lift. Twisting harder bends the blade or breaks it off in the lock.
Do not pry the glove box. The latch and the surrounding dash trim are plastic, and the damage costs more to put right than the key would have.
Getting a Master Key Made
A master can be made even when a valet key is all that remains. The blade is cut to the factory specification for the vehicle rather than copied from the key in your hand, and on chipped keys the new key is then registered to the car.
These are our published bands from the car key replacement cost page, complete job, cut and programmed at the vehicle:
| Key type | Complete job |
|---|---|
| Basic mechanical key, no chip | $50 – $100 |
| Standard transponder chip key | $130 – $220 |
| Remote head key | $160 – $260 |
| Smart proximity fob (push-to-start) | $220 – $450 |
| All-keys-lost surcharge, where it applies | +$50 – $200 |
One honest caveat. On some older immobilizer systems a valet key can start the car but cannot be used to authorise adding another key. When that is the case, making a master is closer to an all-keys-lost job than a simple spare, and the surcharge can apply. We check which system your car has before quoting, so the number you hear is the number you pay. The general economics are in spare key now vs all keys lost later.
Lock work, meaning a seized cylinder or a mismatched replacement lock, is quoted per vehicle after we have seen it.
If Something Is Locked in the Trunk Right Now
If you need what is in the trunk today and the only key is a valet key, do not pry at the lid and do not drill anything. On most sedans the trunk can be opened without damage by a technician, and the master key can be made in the same visit so it does not happen again. That is covered under car lockout service and locked keys in car.
Why Ownership Is Checked First
Making a master key from a vehicle is exactly the kind of work that should not be done for the wrong person. We ask for registration or title and photo ID before starting. That is the standard set through the National Automotive Service Task Force, whose vetting scheme covers independent professionals who access manufacturer key and security data.
The reason is practical. The Insurance Institute for Highway Safety has documented lower theft rates on immobilizer-equipped vehicles, and that protection depends on keys being made only for owners. If you have just bought the car, the National Highway Traffic Safety Administration recall lookup is worth a minute with the VIN while the paperwork is out.
Choosing Who Makes It
Texas licenses locksmith companies through the Texas Department of Public Safety Private Security Program. That is DPS, not TDLR. Ask for the licence number.
The Federal Trade Commission and the Better Business Bureau both warn about locksmith listings that advertise one price and charge another on arrival. For this job in particular, be wary of anyone who offers to "copy" your key cheaply without asking what kind of key it is. A copy of a valet key is the problem you already have.
Mobile Service Across Fort Worth and Tarrant County
We cut and program at the vehicle in Fort Worth and nearby cities including Arlington, Hurst, Bedford, Euless, Haltom City, Keller and North Richland Hills.
Brand detail is on the Honda key replacement and Toyota key replacement pages, and the service on transponder keys. How many keys a car will accept is covered in how many keys can my car hold.
Frequently Asked Questions
Why does my spare key start the car but not open the trunk?
It is most likely a valet key. Valet keys are built to open the driver's door and start the engine while being unable to open the trunk or glove box, so valuables stay locked when the car is handed to an attendant.
How can I tell a valet key from a master key?
On Honda, Acura, Toyota and Lexus the valet key commonly has a grey plastic head and the master a black one. Other makes use a different head shape or a stamp. A key that works the door and ignition but neither the trunk nor the glove box is a valet key whatever its colour.
Can a valet key be reprogrammed to open the trunk?
No. The limit is in the cut of the blade, not in software. A master key has to be cut to the vehicle's factory specification.
I copied my key and the copy will not open the trunk either. Why?
A copy inherits the cuts of the original. If the original was a valet key, every duplicate made from it is also a valet key, even on a black-headed blank.
Can you make a master key if I only have the valet key?
Yes. The master is cut from the vehicle's specification and registered to the car. On some older immobilizer systems a valet key cannot authorise adding keys, in which case the all-keys-lost surcharge of $50 – $200 can apply. We check before quoting.
How much does a master key cost in Fort Worth?
As of October 2026, $50 – $100 for a no-chip mechanical key, $130 – $220 for a standard transponder key, $160 – $260 for a remote head key and $220 – $450 for a smart fob, cut and programmed at the vehicle.
My master key will not open the trunk and the inside release is dead. What is wrong?
Check for a trunk lock-out switch, usually inside the glove box on sedans that have one. If it is switched on, the cabin release is disabled. If the switch is off, check the car's battery, then suspect the lock.
The key goes into the trunk lock and will not turn. Should I force it?
No. A trunk cylinder that is rarely used can seize, and forcing the key is how it snaps. The lock needs servicing or replacing, which is quoted per vehicle.
Tell Us What Colour the Key Is
Call or text 817-674-2304 with the year and model, the colour of the key head, and which locks the key does and does not open. That is usually enough to tell you on the phone whether you have a valet key, a lock problem or a switch, and what a master key will cost for your car.
Article written by the Fortworthlocksmithexperts Automotive Locksmith Team. For mobile automotive locksmith service throughout Fort Worth and Tarrant County, contact us at 817-674-2304.
Locked out or need a key now?
Mobile auto locksmith service across Fort Worth and the surrounding metroplex. We come to you — 24/7.
Call 817-674-2304