OT. Newer Car keys with a chip

Yes. It's a passive RFID thing. Some people remove them from the key and tape them near the lock so that non-chipped keys can be used.

I was surprised when my '04 car wouldn't start with the new key I'd had cut - the engine turned over but wouldn't fire. That's when I found all this out.

Cheers

I learned something today, thanks.

I remember the old GMs that only used a resistor. The guy from the auto repair shop would come and buy a resistor when they had to change the steering column.

Obviously that won't work on the newer cars.

Wondering who else can pick up that RFID...

My Volt doesn't even have a physical turn-key that you use regularly for anything. The fob has a weird-shaped little emergency key you can pull out of it (with difficulty) and use to open the driver's door via a recessed locking mechanism that's not designed for regular use.

Inside there's a glowing blue button with the circle/line ON/OFF indicator you press to activate the car. Unless it's very cold out the engine won't come on (whenever the Volt comes to a stop in normal operation even running off the engine it shuts down and is dead silent, takes some getting used to.)

If the key fob's battery is very low the car won't detect it and you can't start via the button with the fob in your pocket; you have to place it in a special little cubby which is beneath the plastic liner of the center console storage bin. I guess there's some kind of inductive coupling system there that then provides power directly to the fob's ident transmitter instead of the fob's battery.

Or if you have OnStar you can just start the car from an app on your phone. It's kind of neat because you can set a departure time in advance and on cold or hot days say 10 minutes ahead of that time it will bring all the climate systems up and begin cooling or warming the cabin

The chip in my 1996 Volkswagen key was a little block of resin inside the handle part, some sort of passive RFID, due to the cost of replacement I didn't investigte further except determining that without the chip the car would not start.

You can probably glue the chip to the sensor and then use physical copies of the mechanical key part. (the handle on my key opened like a clamshell revealing the chip - about as as big as a PDIP4 but without leads)

Great, I'll spend $2.50 for a key and if it works for me, I'll spend $2.50 more for a second key. (2009 Toyota)

Thanks, Mikek