In the old days a key breaking was strictly a mechanical failure of the metal key, but todays vehicle keys also include electronic components to remotely operate locks as well as an anti-theft device known as a transponder. Outside of Nissan and Chrysler vehicles, the transponders rarely fail, but the plastic cases on all of the remote head keys seem to break quite easily.
When the metal part of the key breaks, it just requires obtaining a new key cut to match the broken one unless electronic components are involved. Dr Auto Lock stocks many common shells for keys containing electronic components when just the shell or metal part of the key breaks. It is far less costly to just replace the key shell than to replace the electronic components as well. This is also true of keys that only contain a transponder chip. At Dr Auto Lock, we can usually replace the shell and reuse the transponder chip from the broken key. Reusing the electronic components usually does not require the reprogramming of the electronic components, making the repair less costly.
Always purchase your replacement shell from a local locksmith, as most locksmiths are not willing to cut keys of unknown materials. Many cheap keys sold online are made of cheap materials that may damage expensive key cutting equipment. We have also found that many of these shells will not properly allow the electronics to fit into them. Once the cheap shell is cut, the scam artist who sold them to you will not refund your money, and usually they refuse to give you a refund even if you did not have the key cut.
The most common vehicles that experience remote head shell breakage are Lexus and Chrysler vehicles. The plastic breaks quite easily on these vehicles and we replace quite few of them. Almost all other vehicles are susceptible to having the metal key blade break after the key has been bent. Flip blade keys used on German vehicles and domestic vehicles tend to break where the key blade is pinned to the remote. These failures require a new remote with electronics and programming. The G.M. remotes are the least costly to replace while the German ones cost the most.
The most important thing to do is to visually inspect your keys weekly. If you see a small crack or fracture starting or if the key is bent, get it replaced immediately. It will cost even more if the key breaks off in the ignition lock. If the key does break off in your ignition, do yourself a favor and call a professional automotive locksmith to extract it. I have replaced hundreds of locks after the vehicle owner or some know it all friend attempted to remove the key, ruining the lock in the process. And finally do not ever try to use super glue to remove the key, it will ruin your lock. The upper key is a transponder key w/o remote while the lower key is a remote flip key.