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Redemption
01-24-2012, 02:18 PM
Hello, and thank you for taking your time to read this.
I have seen the aftermaket push button start for cars and they suck. I have seen people still have to turn their keys to allow the acc. and ignition to turn on then they push a button. dumb!
I have seen where they flip a switch then push a button. Kinda lame.
I would like a single button that when push the acc and ignition will turn on. when the brake is applied and the button is pushed the acc and ignition will turn on and the car will start.
Also this sytem has to work with a remote start in the vehicle. When remote started you get in the vehicle and turn the key so the acc and ignition run, you then press the brake and the
car takes over and the remote start disengages.
Thank you

bill190
01-24-2012, 03:00 PM
The problem with that is all cars are different!

The wiring will be different colors from the same manufacturer for different years for the same exact parts! And may even work differently. They may have the same exact key switch and one year use a green wire which switches ground. Then the next year use a blue wire which switches positive! Then the year after that they go back to switching negative and use yet another colored wire.

They also use different connectors from year to year.

And then some have a resistor or chip embedded in the key. And that makes electrical contact with the key switch. And there may be a separate electronic module which determines if it is a valid key or not. Or it could be part of the main car computer. That changes from year to year as well!

Then older automatic vehicles will start without stepping on the brake. Manual transmission you may need to press in the clutch or place the gear shift in neutral. (For the starter to activate.)

Basically you would need to get the factory electrical diagrams manual for each specific vehicle and model year, they see how everything works for that specific vehicle. (Order that as part of the Factory Service Manual set of books from a dealer. The factory electrical diagrams manual alone for one specific vehicle model and year can be 90 pages!)

Note that newer vehicles can have up to 80 different computer modules in them and 3 different computer local area networks connecting those computers!

Here is a bit on that...
http://www.aa1car.com/library/can_systems.htm

http://en.wikipedia.org/wiki/CAN_bus

http://www.fastfieros.com/tech/why_the_gmlan.htm

Redemption
01-24-2012, 04:10 PM
Bill190 thank u for your reply.

I understand where your going with your reply however I'm looking for a simple solution for a simple problem. No computer, no can, no key fob, no anything. Ill try to explain a little better.

Let's say the wires are red(acc), white(ing), blue(starter) and green(brake). When you turn your key the first turn is for red(acc), the second is for white(ign), and the third turn is momentary for the (blue)starter. You hold the key
only longer enough to start your car it then goes back to leaving only the red(acc) and white(ign) on. From what I've seen the after makert push button is only a momentary switch for the blue(starter).

Which means the button is only for the starter you still have to turn on the acc and ign somehow. People still use their key (which I think is dumb...just finish turning the key) others put a switch
the that connects the red and white so that the acc and ign can be engaged.

I'm trying to find a way to have one button do both. Newer cars have computers that do it for the car. I need something that can do it for me.

One push the red(acc) and white(ign) turn on. One push with the green(brake) applied the acc and ign turn on the the car will start because the blue wire is engaged but only long enough to start the car.

bill190
01-24-2012, 05:55 PM
So are you just doing this for your one car?

(As opposed to this potentially being used for any car?)

If that is the case, you could just use a Parallax Basic Stamp microcontroller.
Connect two push buttons. (On-Start/Off)
And connect three relays as output. (Acc, Ignition, Start) Connect relay contacts to car wiring.

Then just program it to switch on the relays as you wish when one button is pressed.
And relays off when the other button is pressed.

You can program it so when a button is pressed, two relays switch on. And while continuing to hold down the button the 3rd relay (starter) is switched on. And when the button is released, the third relay switches off.

Redemption
01-24-2012, 06:04 PM
Yes... sorry this is just for my car.

That last sentence you wrote is what I want. But I have no idea how to use a microcontroller. That is why I came here. U know way more than I do but this programming thing. If you could help me you would be a god to me!

xanadu
01-24-2012, 07:35 PM
Yes... sorry this is just for my car.

That last sentence you wrote is what I want. But I have no idea how to use a microcontroller. That is why I came here. U know way more than I do but this programming thing. If you could help me you would be a god to me!

It's funny that you already have a remote start and now you want a button too, this is my kind of project lol.

It would be very easy to do what you want to do, if you could control the car by using the remote start/alarm you already have. You will always need to put your keys in the ignition to drive the car, or else you won't be able to steer.

What remote start/alarm do you have?

Redemption
01-24-2012, 08:08 PM
Hey Jon,

The remote start is cool but jumping in to my mini truck and pushing a button is even cooler. And as Bill190 put, having it where I push it once and the acc and ign come on is awesome because I can turn on the radio too.

Here's the thing. I'm going to remove the key cyclider which is the steering colum lock. Where the key hole is on my dash I want a button. A single button! I want the thing to work when the car in not alarmed. I believe I can just wire before the starter kill. Once the alarm is alarmed the starter kill will disable the button. Just as if there was a key.
I have the viper 5701.

Bill190...Can the microcontroller be programed where I push it once the acc and ign come on, hold it down and the car starts and finally push the button twice and the car turns off? I still need to turn it off!

bill190
01-24-2012, 10:09 PM
Bill190...Can the microcontroller be programed where I push it once the acc and ign come on, hold it down and the car starts and finally push the button twice and the car turns off? I still need to turn it off!

You can ask anyone here these questions (I'm not always around!)

Anyway yes you can program it as above. Just use delays in the programming and look for the button to be pressed twice within a certain time frame. Or held down beyond that time frame to start.

To learn about microcontrollers and programming them, specifically the Parallax Basic Stamp, just go to your nearest Radio Shack and they sell them there. It may say "What's a Microcontroller - Basic Stamp" on the box.

Then read the book and play with it. Do the basic steps in the instruction manual. Maybe make some LED lights blink.

Then when you want to try a push button and relay, if you have questions, go to the Basic Stamp area on this forum and there are plenty of people there to help you and answer your questions.

The Basic Stamp is the easiest microcontroller to learn. And plenty of help here.

Have fun!

Redemption
01-24-2012, 10:31 PM
Cool. Thank u Bill190

frank freedman
01-25-2012, 03:50 AM
Bill190 thank u for your reply.

I understand where your going with your reply however I'm looking for a simple solution for a simple problem. No computer, no can, no key fob, no anything. Ill try to explain a little better.

Let's say the wires are red(acc), white(ing), blue(starter) and green(brake). When you turn your key the first turn is for red(acc), the second is for white(ign), and the third turn is momentary for the (blue)starter. You hold the key
only longer enough to start your car it then goes back to leaving only the red(acc) and white(ign) on. From what I've seen the after makert push button is only a momentary switch for the blue(starter).

Which means the button is only for the starter you still have to turn on the acc and ign somehow. People still use their key (which I think is dumb...just finish turning the key) others put a switch
the that connects the red and white so that the acc and ign can be engaged.

I'm trying to find a way to have one button do both. Newer cars have computers that do it for the car. I need something that can do it for me.

One push the red(acc) and white(ign) turn on. One push with the green(brake) applied the acc and ign turn on the the car will start because the blue wire is engaged but only long enough to start the car.

Draw it out as an old fashion ladder diagram w/ the interlocks, time delay relays etc. once your ladder logic is right, then you should be able to port it over to cpu control. You will still have to somehow limit the start time or trash your starter.
Do you plan to use the same button to cut off the engine? That will add a bit of complexity and perhaps some risk.
Oh yeah, how long is enough to start the car. May be worth considering some sort of method to sense that the flywheel is outrunning the starter to tell that the engine is actually running. A human uses sound to tell.Perhaps a load cell w/ a bridge or better and easiest, monitor the starter current (it should be very heavy being a series wound motor) until the load is removed, i.e. the flywheel is turning as fast or faster than the starter. Perhaps consider a watchdog timer to prevent frying the starter in the event of no start. Also a delay time between failed start attempts.

Just couple ideas fer ya,

FF

Loopy Byteloose
01-25-2012, 10:36 AM
Try taking a look at Latching Relays. These come in various varieties, but can be made to toggle ON at the first push and OFF at the second and so on.

Redemption
01-25-2012, 02:47 PM
Thanx for the reply G.Herzog,

I would like to beileve that Im pretty good at understanding relays. However, for this project the relays I have found they would do what I need.
I have called different places and everyone has told me that the best way to go is with a microcontroller.

Redemption
01-25-2012, 02:50 PM
Thanx for the reply FF,

The button project would only replace the key with a button. the starter would not be a problem because I am still manually starting ther car. And yes I want the button the turn everything off.
I believe the controller can be programed to turn everyhting off when pushed twice.

idbruce
01-25-2012, 03:33 PM
One push the red(acc) and white(ign) turn on. One push with the green(brake) applied the acc and ign turn on the the car will start because the blue wire is engaged but only long enough to start the car.


I may be overlooking something, but this does not sound that difficult.

Button is an input into the microcontroller
Break pedal is an input into the microcontroller
Three relays controlled from the microcontroller, acc, ign, start


Loop for input from brake pedal
Loop for input from pushbutton
Monitor the number of button presses

If pushbutton is high and brake pedal is low, switch on the acc and ign. If pushbutton is high and brake pedal is high, switch on the acc, ign, and starter, and discontinue starter when the button goes low. On the next button press, shut off all relays. However, if you push the button without brake pedal input just to listen to music, you will have to push the button to turn it off and then push the brake and button to start the vehicle.

Redemption
01-25-2012, 10:51 PM
Thanx idbruce for the reply,

It is that straight forward. For the most part you have it down.

Ran into some more problems with the brake input though. I am gong to have to leave that part out. And program different momentary codes with the button.
The button is going to have to do everything. If the brake is press before the microcontroller can take over the remote start will kill the car.

Other than that its pretty straight forward. I have never used a microcontroller and that is why I came here. Everybody has helped me out..thank u.
I have learned a lot in these forums, interent, and youtube. I have called a couple of businesses and they have been helpful too. I just need to learn
how to use the microcontroller.

frank freedman
01-25-2012, 11:25 PM
Thanx for the reply FF,

The button project would only replace the key with a button. the starter would not be a problem because I am still manually starting ther car. And yes I want the button the turn everything off.
I believe the controller can be programed to turn everyhting off when pushed twice.

Whatever you end up implementing, it would be a very good idea to install an emergency stop switch which can positively deactivate/shutdown everything under ANY fault. Not my idea, just ripped it off from Siemens, GE, Philips and a host of other major and minor medical device makers whose systems could cause bodily harm from uncontrolled mechanical movements, mechanical end-stop/limit failures, X-ray off failures etc. Regardless of all else we have said, please include this function in hardware as a failsafe.

Frank

Loopy Byteloose
01-26-2012, 09:34 AM
I still suspect that ONE 12VDC latching relay AND ONE button can simply do the job WITHOUT all the complexity of a micro-controller which requires a regulated voltage supply and crystal and output circuitry. It is likely that you are going to have to buy a relay anyway that is driven by the micro-controller.

Essentially, the ignition switch turns on the ignition coil power, enables the starter solenoid circuit, and all auxiliary power requirements.

But if you MUST go with the micro-controller, a BasicStamp is quite adequate. It is your choice. But bear in mind that the micro-controller must be ON at all times to be available for actuation; while the latching relay will not consume any power when the automobile is in an OFF condition.

The brake light circuit would enable a second relay to engage the starter motor solenoid IF the engine is not already running. That is the part of the design that demands some careful consideration.

We have all become so digitally-minded that we tend to ignore some very good traditional solutions. (In any event, I have serious doubts about the inherent safety of your design scheme. It is best to just have a second button for the starter motor to avoid a myriad of starting hazards.)

bill190
01-26-2012, 01:52 PM
I prefer the microcontroller solution. Quite easy to change timing and so forth. Just enter new numbers. Plus more fun!

With hard wired, you need different value components, or there is a limitation to the timing adjustments. And if you make a boo boo in design, you might need to do a LOT of rewiring, order additional components, etc.

My biggest frustration with hardwired electronics always was that I needed a capacitor or resistor of a certain value and didn't have it!

Redemption
01-26-2012, 03:31 PM
This is why I came here! I remember back in the early 00's going back and forth with my guys in the install bays at Circuit City about different install designs. Cool!

Ok G.,
I have thought the relat thing through in differnet ways, yesterday I try to draw up a design and here is the problem I have.
I stll want only one button or switch. I found a on-off-(on) switch. I figured I could easily relay the "on-off' part to "off-on"
this way I could leave the switch on the new "off" and when I get in I flip the switch to the new "on" which in turn would active
the latching relay.

Flip the switch to momentary on and the starter relay would go. Here initself is where I have the problem. Because the switch is reversed
when I go start to car the new "on" or middle switch would reopen the circuit and the latching relay...........


Oh man G.! I just rethought this as I was writing....... It in fact would work. Make the "on" side turn off the latching realy. The middle would do nothing
and the momentary side start the car. Once the latching relay is on nothing will affect it until the switch is back in the on postion. Which turn everything off.


No extra parts needed!

Redemption
01-26-2012, 03:40 PM
Ok Bill190,

I like the microcontroller idea! I want to do it. I think have a little computer doing things would be so cool!
I think for now I'll do the relay thing. This way I can continue with my project. This way I can have more
time to learn this microcontroller thing. I have thought of ways to wire up this controller.

LEDs telling me which cycle Im on and with in a time period having them slowing fade away....so cool!
And of course... I want a button. A single button. A cool LED ring lit button controling it.

As for the power source? If the controller stops getting power does it forget evrything or can I take power
away whenever and reply it? If so Ill have the alarm cut power on the controller so when Im away the controller
wont consume any power.....

idbruce
01-26-2012, 04:00 PM
How about voice control like in the movie "2012". Just say the words:

"Engine Start"
"Engine Off"
"Accessory On"

Loopy Byteloose
01-27-2012, 07:09 AM
I am a bit concerned. The latching relay take a pulse which requires a momentary switch (in some latching relays it requires 2 momentary switches - one for each direction; but I am NOT considering those)

Simply put, it is easy to power up the mains for a car.

The problem child is the starter circuit as it has to sense that the motor has caught and immediately disengage. You have said you want the brake pedal to engage the starter if the engine is NOT running. I suspect that is like a 'golf cart'.

And so, after the mains is ON, the second circuit would be a relay tapped off the brake light circuit. In order to intervene when the engine is running, one would have to sense the output of the alternator charge circuit and IF the alternator is working at the appropriate voltage level - the starter motor would be locked out. That may be a third relay, or maybe a more sophisticated use of the second one.

The primary issue is that this is a switching circuit and power switching - there is a need for logic and no real need for sophisticated micro-controllers. Also, the latch relay provides a means for whole system to be unconditionally OFF when the off condition is set. The darned microcontroller or any logic chips would require an electrical supply AT ALL TIMES.

So the real trick is how to get the idiot light for the alternator to cooperate with your wiring. This lights are actually designed as a resistor in the charging circuit of the voltage regulator - so that the light is off when the adequate voltage levels are provided. One must be careful to NOT change the resistance by a great amount so that the voltage regulator may properly operate.

I suspect that a high resistance tap and the use of CMOS logic (which tolerates 12VDC and above) may provide you with a good sensor tap. And then when the Alternator light is ON, a relay driven by a Mosfet or transistor would engage the starter solenoid with power provides from the On brake light. (The CMOS logic would also be turned off in this context when the mains are off, but I am wary of a logic chip failure would engage the starter motor relay at unwanted and unpredictable times. Hence I strongly suggest the simpler two momentary button system or a momentary On-off-On toggle with pilot light.)

The big caveat is that starting conditions are greatly affected by temperature and weather (including humidity). It is just easier to have a human control the starting and disengage than it is to try to provide proper timing for all climatic situations.

Loopy Byteloose
01-27-2012, 03:36 PM
After pondering my suggestions, it seem like the whole scheme could be achieved with One 10amp 12VDC latching relay, a resistor or pot, and a TIP120 or larger. At least on older cars without sophisticated lock out systems.

Kievlanin
01-31-2012, 06:06 PM
Is anyone here drove a new Toyota's?
For my Prius, all I need is to keep my key in the pocket.
I still have to push button to let my car know that I want to drive it....
When I am leaving the car, I have to push button again to tell him Goobye!

Just a thought....
Sometime we trying t develop a bike or something that is exist already.
Improvements? Maybe?

Redemption
02-01-2012, 11:04 PM
Sorry I've been away; busy.

Kievlanin, I have ordered the parts needed to get the project going. I have a person that is going to write the program too.

What you want to do is the same thing I'm trying to do. The FOB is just something that will send its own signal just
like the remote will send a signal in my truck. Once I get this down I can write you back if you like?

Kievlanin
02-02-2012, 11:05 PM
We all busy, no complains.
Sure, do write how you accomplished the project.
Can you share with me who helped you with the code?
I am myself have hard time with programming.