[vigilans]

Did you get a genuine key? I never had one fail on me.

The immobilizer is the single best piece of technology for preventing car theft. If you create a backdoor for bypassing it, you'll end up like Hyundai/Kia which decided to sell cars without the immobilizer in recent years and which have turned into a joke in the minds of potential customers.

It does not require a battery in most cases and is separate from the keeloq system that controls your car's doors.

[SV_BubbleTime]

The Stellantis systems I’ve worked on have a nice feature that there is a battery for the proximity use, that you can keep the key in your pocket and press the button to run the car, as long as the key is within the four or five proximity sensors you are fine.

When that battery dies, you can press the directly to the start button and it uses a “receiver powered transmitter” RFID close proximity to start and run the vehicle.

Most people don’t know this, so when that battery dies they panic and suffer.

[giobox]

This technique of pressing the dead key to the starter button works for quite a lot of brands, not just Stellantis vehicles. Always worth trying if you are in a "keyless" car with a dead key fob battery.

In my experience virtually everything made in last 15 years will either support this RFID backup or have a spare physical key hidden inside the keyless fob.

Lots of them will even let you press the dead key against some part of the exterior to unlock the doors too.