Starting car using computer..

**ThunderStick** · 01-10-2008, 04:05 PM

I am trying to develope a keyless system for my car using the computer. My carputer has been running pretty solid now for about a year and I feel comfortable with the idea of it starting my car.
My thought is to use a USB memmory stick as a key. It would contain a specific file that the computer would look for when it is plugged in. If the file is not recognized the computer will shutdown the car with in a few minutes.
What would happen is this.
(1) Turn on car power with on/off button or switch-->
(2) Press the start button on the car-->
(3) Computer powers up as normal carputer would-->
(4) After started you will be prompted to insert your memmory stick-->
(5) If no memmory stick is inserted or you dont have one you can enter a password instead-->
(6) If niether the password or mem stick are used then the car will turn off with in 1 minute of the prompt screen appearing-->
(7) Turn off the car by simply pressing the power on/off button or let the car stay parked (determined by information from GPS) for a preset amount of time.
Most of these functions I can configure using ROAD RUNNER, no other software needed. The problem I am having though is polling infomation from the GPS reciever to determine that the car is parked. Or is there a better method for doing this other than using a GPS reciver?
I would also like to be able to trigger the steering whel lock from the computer. By this I mean I want to send voltage from the computer once the password is entered or the memstick is inserted to unlock the steering wheel.
How can I do this?

**creature0077** · 01-11-2008, 12:46 AM

I'm curious why you would want to bother testing if the car is parked? Most ECU won't allowed the cars to start unless they are already in park or neutral.
Let me make sure I understand this correctly, you want to build a remote starter right or do you want to built something more of a security lock?

I'm doing something similar but it's a hardware hack. I'm just going to cut the wires for the starter and put them to a momentary switch to start. So when people get in the car they have to put the key in but it will only work all the way up to "on" not to "start" since the wires were routed elsewhere to a switch I have hidden.

I'm no car expert but to lock the steering wheel the key had to be in the lock position then taken out then you manually have to move the steering wheel till it locks right? It's usually not locked until that happens or until the tires move. At least that's what I thought it is for all pre 97's at least.

Maybe I just missunderstood a bit.

**ThunderStick** · 01-11-2008, 08:56 AM

Maybe reading the post a little closer will define what I want to do. This is not a remote starter but a security feature that will shut the car off if the password entered or USB key is not inserted. The reason for this would be that a USB stick is much easier to replace and a password is easier to figure out. I own a jaguar and just finding a lock smith to make a new key is difficult. If I was out in the middle of nowhere and needed a key made, I would be *** out of luck. This happened to me recently and that spurred the whole idea.
I tought about it before but now the push is on and I feel as if I need to get this done sooner than later.
As for the steering wheel lock you are right it is key operated. Mine is non-functional anyway so there is no worry there. Plus the ignition switch will be removed when this application is put completed.
What I really need is a way to interrupt the circuit for the cars power (or keys on position circuit). My idea now is that when the computer starts the 12v from the PC will trigger an automotive relay completing the circuit and allowing you to start the car but once the windows prompt comes up to enter the password or insert the USB stick if not entered correctly the computer will shutdown and the car will turn off with in 1 minute.
The only problem I have is keeping this circuit closed if the computer were to freeze and shutdown or not start up at all. I suppose a hidden switch would work or even a seperate keyed ignition hidden somewhere.

**DroStar** · 01-17-2008, 04:48 PM

You could use a normally closed relay and energize it when you want to cut the power. But then a thief would have to do to get around the system is cut the power to the relay or the computer. Security vs convenience. Using a normally open is more secure but will cause a big inconvenience if something goes wrong with the PC.

As for the steering wheel lock, they are usually mechanical so you'd have to rig up a solenoid to engage the lock. If it is electrical already then just tie into it.

**turbocad6** · 01-17-2008, 05:09 PM

I would approach this a bit different. I would install a remote start module that takes care of the actual starting. this way, when you hit the button on the dash or even the remote button, the car will start, with or without the PC, but, if you step on the brake pedal or try to move the shifter the car would die. when the PC comes up, it'll ask for the thumb drive &/or password. this would then override the kill when stepping on the brakes, & switch from the timed running of the remote start to a permanent on throughout that ign cycle.

**turbocad6** · 01-17-2008, 05:27 PM

oh, btw, I did this similar, but without the password thing, I used the fusion brain to control the remote starting by interfacing it dirrectly with a spare remote. the idea was so I could connect to my car through the net & remotely start the car. I did hook it all up & get it working at one point, but never finalized yet in that install & the fusion brain has gone through a few updates since then, gotta get back into that end of it really.

**tmonroe** · 01-17-2008, 06:43 PM

Am I missing something here? The steering lock/transmission lock are a security feature of the car. With your setup, you'd need to leave the key in the car all the time in order to drive it - and the transmission and steering wouldn't be locked so your car would be less secure, not more.

I'm not sure about how to determine if the car had moved, but if it were me, I'd get a second GPS unit specifically for determining when the car is moving (mapping software seems to have a tenancy to lock GPS receivers so that nothing else can get see the data). Then you just need something like GPSMAN (its hidden in the list of free GPS downloads http://www.maps-gps-info.com/fgpfw.html ) to write the data to a log file. Finally, parse you'd parse the log file (I could probably figure it out in VBScript), and look for changes in position that are greater than the inaccuracy of your GPS unit.

I could see having problems with this if, for example you were parked in a city, near tall buildings with very limited GPS reception. Whenever you missed a GPS signal, it would think the car was moving, and shut it off.

Why not just make a spare key, and hide it someplace you're not likely to lose it - like your wallet?

**AcuraTLFan** · 01-17-2008, 10:22 PM

I wanted to start a project like this using RFID tags and a BASIC Stamp kit...probalby be no more then ~$50. But i always worry about system security and dependability.

**ThunderStick** · 01-19-2008, 01:08 PM

OK, I think I finally came up with a plan, thanks to Turbocad6
The remote car start is an excellent idea. This will be the route I am taking. The only problem I see, is that the battery may die in the remote and then what?
Since I have had a remote car starter/security alarm for a while now, I think it is time to hook it up and give this idea a try.
THANKS FOR HELP
I will post updates once completed and working...

**turbocad6** · 01-19-2008, 02:56 PM

well, what you want is the module... once you hit the "start" button, the module will take over & go through the ign cycle, starting & rpm monitoring etc. it would do all the work for you in a sophisticated way that so much beats having to hold a button to crank...

many remote start modules will just need a trigger to start the sequence, a ground pulse on a circuit... now if you just hook up a button to this circuit, then any time the button is pressed the car Will go through a startup routine, but of course no one would be able to actually just drive it away because at that point it's only in a temporary running routine that will either time out or abruptly shut down if any security is breached.

if your going to use an all in one start & alarm,. then they usually do not have this ground pulse start request because it is handled internally within the module itself... this is the case with the one I did. my solution was to embed a spare remote for the system into the car... it can be powered by the car with a regulator... most are now 12v anyway really, so dead battery in a remote is not an issue.

since your steering lock is disabled anyway then your all set, all you would have to have your security override do for "drive mode" is to just keep the 3 or 4 relays activated throughout the cycle... if you still had the steering lock then it would either need to be controlled by a solenoid or disabled... steering locks are a good security measure, but in the end no one would even know that yours isn't locked anyway, so a steering lock bypass isn't the worse thing really as far as security is concerned.

to have your password or usb key enable "drive mode", this is best done with a diode circuit, so it keeps itself activated, once the diode completes the circuit the relays are then just energizing themselves, so you won't be driving down the road & have it have any chance of it just dying no matter what the computer did at that point... it would then stay activated till you shut it down... shut down could be more tricky than startup really at this point... you will need to kill the ign so the relays open... doing this through the start button will take a little creativity, but should be simple enough, what I would do is use another relay that if the ign is already on, then a start button press will open the ign circiut... if you need any help figuring out the wiring lmk, I'd be glad to help

I'm sure that this could be done more sophisticated, instead of diodes & relays you could build a pic & circuit board & make it all electronic, but that's where my own limitations come in, relays & diodes are right up my alley, but programming pic's & building complicated electronic circuits are a bit out of my own scope of what I could do myself. really I think analog circuitry would be more reliable & easier to live with than custom funky electronics anyway at this point... even if your PC was dead you wouldn't have any crippling of the car, & it should be as reliable as factory if you solder everything & use good relays that are not overloaded... you could always have an emergency bypass in case your usb key or password enabling was ever unavailable at some point too

good luck with it.. key ignitions suck once your used to keyless, I would never want to go back to having to dig for a key & stick it in & turn it manually... I love keyless & have been keyless for a while now... keyless is cool & very convenient