relay to start the car

I was wondering is it possible to start/off the car, with a relay. Or if I have the car starter kit installed, can I hack the car starter kit and use a relay to trick that it was send from remote or other solution to start the car. Thanks!

If I understand you correctly you want to start the car without the key or without the use of a remote starter's remote. Some remote starters have a circuit which when pulsed to ground will activate the starter and start the car. It is normally used for integration with an alarm system, wherein an alarm's auxillary channel is used to activate a remote starter instead of the remote starter's remote control. There are also specific remote starter units which don't come with a remote and are designed to be triggered by another unit. I hope this helps.sparky

So I need to buy a romet starter, inorder to start the car without the key. Here is what I wanted to do, I want to use my laptop to start the car, and computer do send out a 5volt out from the parallel port. I got the lock and window control by the computer already. I want my computer be able to start the car. So I was wondering is there an easy way to do this, like as simple as the window of the car, where you just use some relays to trigger the window. If not, I need to buy a remote starter kit, and install it right? Now how do will I use my computer to start the car with the remote starters. Thanks!

The best way to do it is to use a stand alone remote starter as described. That type of unit will accept a signal (usually a ground pulse on a specific wire) and activate the remote starter. To construct relay circuits which power all the neccesary wires in the correct order is too much work and difficult. All the neccesary logic circuits and safety measures are already in place in the remote starter. You would still have to construct a circuit that will send a ground pulse to the starter after receiving a 5 volt signal from your computer. A qualified electronics technician should be able to fashion a micro-processor circuit to accomplish that. You may also have to add some extra modules to the remote starter to interface with any vehicle anti-theft systems, depending on your vehicle's requirements.sparky

That might not really work, since remote starters usually start with a remote key, which sends a different code each time you hit start on the remote. TO have your computer(laptop) start the RS unit, you could achieve your goal if you send the same signal yoru key would send but that is impossible unless you know the exact algorithm used in the remote key. It looks like you want to hard-wire a relay to accomplish this. For that, it is really not a "remote start" but a relay-start really. For that you can do it like sparkie mentions, by adding a microprocessor that duplicates the powering sequence that the RS unit would do. Also try to keep within the safety measures that the RS unit is built into. If you successfuly get the right sequence of powering, you should also set your software to detect a tach signal or a voltage signal (like the RS unit would do) and stop cranking at the right time or else you could ruin your motor. GOod luck and have fun!

As mentioned your easiest way is to get a remote start installed and just hit that from your laptop. Just make sure the remote start unit you get has a (-) activation input meaning you can remote start it by other means than a remote. You might end up with what's called an add-on remote start which doesn't even come with remotes or if you want get one that does have remotes also since it would be nice to have just make sure it also has an activation input.. Good luck, Mike