Push Button Start with Passive Device Key wanted

[matty b]

So next time, before you call BS, why don't you give the guy a chance to explain. He said he was going to post a schematic but the way you jumped on him, I'm surprised he responded at all. I don't think I would have.

Look at the last sentence, it starts with the word IF, there are tons of guys that like he said just use the button as a starter button and thats it. Im on alot of electronics forums and maybe 1% of them are in the same league as this. As soon as he posted what he did I also congratualted him on a cheap simple setup. You wouldnt believe how many guys will say that they did something like that and never come back to even show the setup functioning let alone how its made. So although it may come off a bit harsh I didnt go all the way by saying it was BS just that it would be BS if he didnt back up the claim.

jlmccuan- suprisingly the company that makes the cheapy alarm you bought actually makes an RFID push button start kit as well and Im talking with them on how to obtain it or who their supplier is in the US so everyone may not have to go through the trouble of modifying stuff if this can be bought ready to go. Either way good job. Also I gave it some though and figured that you could get a latching relay for the ignition circuit that is pulsed by the alarm on one channel and setup the starter so that when you hold the button for a second a second channel is activated. Some alarms allow for this such as a quick tap unlocks the doors while holding the button for 2 seconds unlocks the trunk. This could be modified for the igniton as well so that the latching relay is controlled by the door unlock and the standard relay is controlled by the trunk release. Only modifications necessary would be to open the alarm box and find the transistior that is trigger by the fob and hard wire off it for a switch. Other way would be to open the fob and hook a switch to the fob button and wire in a voltage drop to the battery in the fob so it is powered by vehicle volatge and not just the little battery in the fob. Im going to go by the alarm/stereo shop today and get a cheap 3 channel alarm and play around with it and see if I can get it to work for under 40 bucks.

[tellyv]

I'm very interested in this, I only want to use it for ignition and accessories, any easy ways just for that?

[matty b]

what exactly do you want it to do? turn the car on when you walk up to it and just hit a button to start the car? if so thats really easy, lemme know if thats what you want and Ill draw you a schematic

[tellyv]

what exactly do you want it to do? turn the car on when you walk up to it and just hit a button to start the car? if so thats really easy, lemme know if thats what you want and Ill draw you a schematic

yes thats exactly what I want.

[matty b]

This is based off of Chevy Color Code but as long as you can identify the different wires from your original ignition switch this is how to set it up. Remeber that this will turn the car on when you walk up to it so there is no way to turn it off with out walking away from the car. This could be potentially hazardous if something happens and you need to turn the car off. If you want, you can put an SPST switch on the ground coming from the RFID relay that you normally keep on but it can be switched off in the event that you need to kill the car. It can be a small microswitch since it wont be carrying any heavy current through it. Basic function of this setup is as follws, The RFID relay is a switch that triggers the POWER RELAY and the START RELAY. The POWER RELAY powers up the IGNITON and ACCESSORY circuits only. The START RELAY handles the STARTER and the ground trigger is handled by a momentary switch of your choice. This can be an S2000 start button, Z8 button ect. This does not have provisions to light up the button however it could be setup if you splice off of the IGN or ACC wires and hook it to the light. This will keep the light lit when the car is turned on and could indicate that those circuits are hot. With a latching relay you could hook it up so that the light is on until the STARTER is engaged and then it turns off after you pressed the button. This is expensive though and wont keep the STARTER from being engaged a second time so its purely esthetic. This should handle what you are asking for though and is pretty simple in its operation. Hope that helps

PS the 20 amp fuse for the starter is just a recommendation, based off of how much current the starter solenoid draws it may need to be bigger but as it is, it is fused at the same size that most cars are for the starter and it should work fine.

[matty b]

BTW I got off the phone that handles our alarm and stereo installs and he told me that he has a "brain" as he calls it that can in fact be programmed to do what we need with no need for special latching relays or anything since it is programmable to do it out of the box. Im getting one on moday during lunch and Ill play around with it to see if I cant get something working by dinner time. Stay tuned and Ill get some pics of it

[viper11]

hey
matty

do you know what brand/model the alarm is???
the only ebay rfid alarm I found is $32.95 http://cgi.ebay.com/ebaymotors/ws/eB...MEWA:IT&ih=007
jason

[Tom 72RS/SS]

Mattyb, I'm eargerly watching your posts as finally someone has made progress in providing us with a "Push to Start" feature that's safe & secure at minimal $$. Keep it coming.
I personally know only a little about electrical systems but I so want to do this!

[jlmccuan]

http://cgi.ebay.com/ebaymotors/RFID-...QQcmdZViewItem

This is the one I used, but it does require some other additions to meet what I wanted.

[matty b]

yeah my way is gonna use a normal alarm that should be in the $50 range and Im gonna use one of those masterlock rfid relay to handle the security. If all goes according to plan I should only have 3 relays; 2 normal bosch relays and the RFID relay. Also I can also use the RFID relay to turn on a doorlock module that I can use to hook to small waterproof buttons by the door handles to unlock the doors yet be dead if you dont have the fob. Its a total aftermarket version of a new corvette or infinity for less than $200. Im pretty excited myself and have to hand it to everyone that has chimed in with different links to the parts necessary.

[Tom 72RS/SS]

So how hard would it be to install power door locks to benefit from the alarm feature. Maybe use a later model setup to actuate since my 72 never had that accessory?

[jlmccuan]

I had to add central locks and actuators. I think it was $30. Got the last details working last night. Ignition and accessories have no power until RFID is present. Doors lock and alarm is armed when RFID is removed or button on fob is pressed. I did elect to use the shock sensing and starter interrupt. I'll try to summarize the functions below.

With RFID not in range or manually armed.

Doors lock.
Fuel door release disabled
Trunk release disabled
Push to start button disabled
Accessory circuits disabled
Alarm enabled, triggered by shock, tilt, opening of door, etc.

When RFID comes into range

Doors unlock
Fuel door release enabled
Trunk release enabled
Courtesy lights come on for 3 minutes
Push to Start button enabled for 3 minutes
Press and release of Push to Start turns on accessory circuits
Second press and release of Push to Start turns off accessory circuits
Press and hold (4 seconds) of Push to Start engages starter until button is released
Subsequent press of Push to Start kills engine and shuts off accessories

I have simplified this a little because I have some other logic in the start circuit that most people won't want to use. For instance, the starter doesn't engage until the engine oil pressure is over 30psi. After a 3 second delay in the press and hold of the Push to Start, a solenoid valve releases oil stored in an accumulator, preoiling the engine. The transmission must be in Park or Neutral and the brake must be depressed for the starter to engage, as well.

The point of all this is that it is possible to to do everything with an RFID signal and one momentary contact switch.

[matty b]

would you mind showing how you got the delay relay integrated into the setup? Im trying to get my head around how it actually functions and a quick diagram would help me figure out exactly what you did

[jlmccuan]

I just ran a delay relay parallel off the momentary switch. Since you need the power to the ignition while cranking the starter, it's just a matter of delaying the starter so you can switch the ignition and accessories on or off without the starter engaging when you don't want it to. For example, without the delay, the push to start button would engage the starter when you pushed the button to kill the engine.

[matty b]

forgive me if this is obvious but what keeps the ignition from turning off when you press the button for the starter the second time?

[jlmccuan]

Press and hold to to turn on the ignition and engage the starter. When the switch is released the starter stops and the ignition remains on until the switch is pressed and released again.

The main function of the switch is to provide a negative pulse to latch and unlatch the ignition/accessory circuits. Secondary use is provided by holding the switch until the delay relay times out and provides power to start relay.

So, the RFID provides access to the interior of the vehicle through the central lock system and power to the Engine Start button which cycles the power on and off to the ignition and accessory circuits with sequential activations of the momentary contact and also power to the starter relay by pressing the switch for more than 4 seconds.

[matty b]

I got that part but when you press and hold the button for start it applies a negative trigger to the ignition latching relay which I would think would turn off the latch and kill the ignition. Is the start relay setup in such a way that it keeps the ignition latched on? Thats what Im struggling to follow. How are you blocking the second pulse back to the latch when holding it for start?

[jlmccuan]

Maybe we're losing the translation in the operation. The first time you push the button, you hold it and after the delay, the starter engages. There is no second pulse unless you release and push a second time which would turn off the ignition. Push and hold to turn on and start, push again kills. Sorry I'm making this so hard, it's really not that hard.

[matty b]

ohh I get it now ok I was confused about how you had it setup. Your setup is kinda like the watsons setup although yours is better cause it doesnt necessarily engage the starter as soon as you press it. My setup will require two presses of the button one for igniton on and a second for the starter. This whole time I thought thats how yours was working but I guess I was mistaken

[jerome]

so with his, you have ignition as soon as you are within range of the car you have ignition, and its not possible to sit in the car with it completely off without having some sort of manual master cutoff switch.