A key breaks inside the ignition or door lock for a combination of reasons: metal fatigue from a worn or bent key, excessive torque applied to an already worn cylinder (particularly when the steering column lock is engaged), a jam caused by debris inside the cylinder, or the key being forced into a position it was not meant to be in (like trying to start a car that has a steering wheel bound against the column lock).
The immediate instinct is to reach for pliers or tweezers to pull the broken stub out. This can work if the stub is protruding far enough beyond the face of the cylinder to grip. But if the break happened inside the cylinder or at the face, gripping attempts typically push the stub deeper, or worse, mar and damage the stub's surface, making it impossible to extract with professional tools afterward.
Do not use superglue, WD-40, or stiff wire to attempt extraction. Superglue bonds the stub to the cylinder wafers, destroying the cylinder and complicating extraction. WD-40 is a solvent that can swell rubber seals in the cylinder. Wire and makeshift hooks typically either miss the stub or push it deeper. Call us, and do not attempt further extraction until we arrive.
Professional Extraction Techniques
We use a set of specialized extraction tools designed specifically for lock cylinders. For key stubs that are partially accessible, a hooked extractor or serrated extractor is inserted alongside the stub, the serrations grip the key's blade profile, and the stub is withdrawn with a controlled pull. For stubs broken inside the cylinder proper (wafer chamber area), a broken key extractor set with multiple hook and spiral profiles is used, inserted under low illumination to feel for the stub's edge.
For particularly stubborn stubs -- those that have been pushed deep or broken with the key rotated off the LOCK position -- it may be necessary to partially disassemble the cylinder. On most vehicles, the ignition cylinder can be removed without steering column disassembly by releasing the retaining clip with the correct release tool and withdrawing the cylinder plug (with the stub inside) for bench-top extraction. This approach is substantially more reliable for deep breaks and takes only slightly more time.
Once the stub is extracted, we assess the cylinder for damage. Wafer tumblers are sometimes chipped when a key breaks, particularly at the break point where the metal fractured. If any wafers are damaged, we replace them before reassembling and confirm the cylinder operates smoothly with a new key.
When Extraction Requires Cylinder Replacement
In some cases, extraction damages the cylinder beyond repair, or the cylinder was already worn to the point of needed replacement. This is actually more common than expected, because keys often break inside cylinders that are already worn -- the increase in friction from worn tumblers is what caused the extra torque that broke the key in the first place.
Cylinder replacement after extraction is a straightforward additional step. We carry replacement cylinders for the most common vehicle makes and can rekey the new cylinder to match your existing working key (if you have one), or proceed to cut new keys and program the transponder at the same time. The cylinder replacement typically adds 20 to 30 minutes to the service time for most vehicles.
Door Lock vs. Ignition: Different Approaches
Broken keys in door lock cylinders present slightly different challenges than ignition cylinders. Door lock cylinders are usually smaller (fewer wafer positions), but they are also less accessible -- they sit behind the door handle escutcheon and may require removing the door handle or trim panel to gain working access for extraction tools.
On most vehicles we can extract broken keys from door locks without panel removal using extended-reach extraction tools through the lock face. If the key is deep or heavily broken, we may remove the door handle escutcheon (a 10-15 minute task) to access the cylinder from a better angle. Door lock cylinders that are damaged during extraction can be replaced independently of the ignition cylinder -- you may choose to have the door cylinder rekeyed to match the ignition, or accept a two-key situation (one for ignition, one for door) if budget is a priority.
When You Need This Service
The key blade snapped inside the ignition cylinder and the stub is not protruding
The key broke in the door lock cylinder
A portion of the key broke and part is lodged in the trunk lock
You attempted self-extraction and pushed the stub deeper
The break point is at the bow (head) of the key, leaving the blade inside
Frequently Asked Questions
Should I spray WD-40 into the cylinder to lubricate it before you arrive?
No. WD-40 is a solvent-based product that may displace oil from the lock but leaves a residue that attracts debris. It can also swell rubber o-rings and soften plastic components. If you feel the need to add lubrication to a sticky cylinder, dry graphite powder (sold at any hardware store) is the appropriate product. But for a broken key situation, do not add anything -- leave the cylinder dry and in whatever state it is in.
Can you extract the key without breaking the ignition?
Yes, in the vast majority of cases. Our extraction tools are specifically designed to grip the key without contacting the wafer tumblers. Cylinder damage during professional extraction is uncommon when the correct tools are used.
What if only a tiny chip of key broke off?
Small chips (less than 3 to 5 mm) are actually more difficult to extract than larger stubs because there is less blade surface to grip. Magnetic tools are ineffective on most modern key alloys (zinc or nickel silver, both non-magnetic). We use fine-tipped hooked extractors under illumination. If the chip is truly microscopic and not impeding cylinder function, it may be reasonable to leave it -- but this is a case-by-case assessment.