Can I use my Galaxy S3 phone as a key fob on my Pontiac G6 2007?
Unless some electrical unlocking and/or engine starting system is already built in it will certainly need various modifications to the electronics and electronics lock or a complete makeover of those to make this possible.
I think you will get a more useful answer at your local tuning store along with an estimate what this might cost.
A general problem even for existing "keyless" systems is that those things send an encrypted signal on a certain frequency which mobile phones just can't do. So this whole thing would have to be refitted with bluetooth or internet which is ~well, not secure at all.
it will not be cheap solution, as Dalsan mention Viper there are some other services.
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If you are talking about using your phone as a device to lock and unlock your car, it really depends on what is in your car to accept such a setup. I know that some expensive third party security systems like Viper has the ability to connect your phone to it to arm and disarm the alarm, as well as start the car.
We would need to know what type of system your car has. Look for a manual in the glove box to see if there is any mention for using your phone to connect to the car.
Do you mean can you drill a hole through your S3 attach a chain to it then dangle your keys from the chain?
He might be referring to using S III to unlock the car as one does to remotely unlock a car without inserting keys.
Wow, someone must have peed in your post toasties this morning!!! Thanks so much for such a sarcastic reply, it made me giggle.