In locksmith terms
Push-to-start replaces the mechanical ignition cylinder with a button. When you press it with your foot on the brake, the car checks for a recognized smart key in the cabin. If the immobilizer trusts the fob, it powers up the ignition and starts the engine electronically.
There is no key turning a tumbler, so the security check is entirely electronic. The fob's encrypted identity, the proximity antennas, and the start system all have to agree before the engine runs.
In plain English
Push-to-start means you keep the fob on you, step on the brake, and press a button to start the car. No inserting, no twisting. The car confirms your fob is inside and then lets you go.
It is a convenience feature built on top of the smart-key and proximity systems, not a separate kind of key.
What to do if the fob battery is dead
Most push-to-start cars have a backup. Many manuals tell you to hold the fob against a marked spot, often the start button or a tray, so the car can read the chip up close even with a dead fob battery. Then press the brake and the button as usual.
If that does not work, the issue may be a failed fob rather than just a battery. A locksmith can supply and program a replacement and cut the emergency blade so you can still get in.
Still have a key or fob question?
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