I'm completely new to circuit building, but I've read up on it for decades now. Finally I have a need for it.

My remote start on my car uses a different fob, and I want to be able to start the car with my OEM fob. I want to be able to start the car by unlocking and then locking the car within two seconds. This means that to trigger the starter unit, you have to at least be able to unlock the car first. This would also allow me to start the car using only my door keypad!

The starter unit can be triggered by two ground signals within 2-seconds

I figure I would need a switch to first be "flipped" by pressing unlock, and then "flopped" by pressing lock. Each action should close the circuit from the starter unit to ground. If you don't trigger the "flop" within two-seconds it should automatically reset.

Any thoughts on where to begin? As well, do you have a preferred software/app for making diagrams?

 

Do you care if locking and unlocking the car within two seconds would also start the car?
That would make for a simpler circuit.

 

Hm, I'd rather prevent unintentional starts. I believe that the way the car accomplishes locking/unlocking is a simple pole-swap. Since the door lock actuators have only two wires... So if I see which way the current is flowing when unlocking, I can use that to distinguish locking/unlocking.

For instance:

Locking does nothing, blocked by diode.

Unlocking starts the 2-second timer. It also flips a transistor that can only be triggered by the reverse current, meaning the action of locking.

Each input should connect the starter unit pin to ground momentarily to trigger it.

 

EDIT: I do have a useless button on my FOB: Panic.

This sends a signal to the computer, and the response is to trigger the horn and parking lights on and off. I'm wondering how I could manipulate this as a signal when the car is off and to return to regular functions when the car is running.

 

This sends a signal to the computer, and the response is to trigger the horn and parking lights on and off. I'm wondering how I could manipulate this as a signal when the car is off and to return to regular functions when the car is running.

Likely the only way to do that is to reprogram the computer.

 

Yeah, I miss tinkering with old cars that were all analog and....what's the opposite of discrete mounted components?

Anyway, I found that the Lighting Control Module is responsible for the panic response. It flashes the lights and honks the horn repeatedly. I found there is a wire from the LCM that is a signal to trigger the horn. Unplug that, and when the alarm is activated you get no horn. However...you get regular 1-second interval pulses from that pin.

So I could trigger the starter using this horn pin, I would just have to have some way of differentiating pressing the panic button and smashing a window then opening the door.

Tough, I know, but it would save my lock actuators from unnecessary wear.

 

So I could trigger the starter using this horn pin, I would just have to have some way of differentiating pressing the panic button and smashing a window then opening the door.

Do you know where the receiver for the remote is located?

 

I don't, I can search. I'm wondering if there's a difference in the signal that the LCM receives if it's triggered by a perimeter breech vs pressing panic. Hmmmm

 

Do you know what kind of RS you have in your car? I am wondering if you already have it built into the RS? Not all but some have them setup already where you can do a ONE WIRE FIRE. What this would do is sense a Triple output from your cars OEM remote and after doing so would start your car?

Tjere is only issue with what you want to do. Your OEM remote is limited on range. IF your aftermarket RS is of any good brand it would out range your OEM by 3 to 4 times the distance or MORE.

Why are you worried about your OEM remote? When an aftermarket RS is installed it should take over the controls of your car OEM system. So only Remote you would ever need is your Aftermarket RS remote.

Now if you have one of them Single Button RS. I am sorry there are some that can do the OEM 1 wire start and others don't. If that is the case, I would really just go and have a better unit installed. You can get them off the Auction sites for really cheap money. In fact I am a person that would rather the OEM RS would either pick up the pace or leave it to the Aftermarket system all together. I mean Why would I want to have a OEM system that only starts my car 2 times at 10 min for total of 20 min, won't start again until I start car with Key...

My RS, I can start car, it will run for as long as the time i set it for, Even forever if I had it set to do so. (Until the Motor died or ran out of gas) I can set it up to start every 2, 4, 6 hours, I can have it set to start if the Temp gets to low, I can drive to the store (Car still running (Pit Stop)) and Press my RS button and turn my car off motor still running, get out lock doors, go in get some milk or early AM coffee on my way to work. (This makes it so I don't have to over work my Starter) OEM RS, start car to warm up before leaving for work, Drive to store, Turn off car, get out lock doors, start car with OEM RS and hope that I can get my items and back out to the car before the 10min is up or remember to extend it another 10 as long as I am within seconds before it was to turn off. If you do it to soon it starts that new 10 say you had 4 minutes left your total time would only be 16 min. Then there is the ability to set a Turbo Timer if my car had a Turbo that I needed to cool off. Best of all mine has 3000ft range, where the oem is 300 some are moving up in range and some can do maybe 500 however that is CLEAR line of sight. Mine is 3000 even though buildings. Sure would lower range if behind steel and deep concrete.

I have installed many many Aftermarket RS, There are so many things you can do with them that the OEM just can't do. They are or have moved up some with the ability to run HVAC and turn on your Rear Defrost. But Aftermarket has been able to do that for MANY MANY years...

In the end. You could almost do the install your self. I mean the wiring has already been done for you once. IF it came down to doing a new install of a better RS. While un-installing the old one install the new one. Hardest part of the job has been done..

James

 

What do you mean one wire?

I have to thank you for all of your insight and the fact that you "get it". Few people, including my significant other, see any benefit to starting before getting in the car. You just can't tell some people the priceless benefit of never sitting in a car that has stale air and having to wait for he accessories to start up and the idle to drop.

You nailed it, my favorite benefit. I can park, hit the start button, pull the key out and lock the door and run into the store, all while my music and HVAC never skip a beat. Shutting down a car and starting it is just sad and wasteful. It's like putting the party on hold just so you can grab some more chips.

As for range, I live in Dallas and was surprised by the range. I parked in a lot that is about 1/4 mile from the Reunion Tower, AKA "big light up ball tower". I went to the observation deck 500' up. It was 45° out, and I was suffering like a dog. It hit me....hey...I can see my car from here. I pressed the button and two seconds later I saw the lights come on and dim as it turned the motor. I traveled down, took the shuttle back and rested my butt in the toastiest coziest shelter from the cold.

The reason I don't want to use the RS fob exclusively is that I drive a Lincoln Town Car. It has memory seats and genuine Corinthian leather. The two seat positions can be linked to two key fobs....only OEM of course. I never want to give up the automatic memory recall function. For instance, sometimes on long drives I'll adjust the seat somewhat, or I'll get out and adjust the seat all the way forward to retrieve something in back, who knows, I just tend to move the seat. Bottom line I want my seat, mirrors and pedals in the same place every time I open my door and my significant other wants the same for her fob and position. Heh.

Thanks so much.

 

Sorry for the Delay on the Reply.

One wire, On some Remote start there is the ability to have info from your OEM alarm start your car. This can be setup in a few different ways. In most cases it is a single wire that detects the input of your cars Door locks. Press lock 3 times in a row would tell the RS that you want to start the car...

Now the only issue with this. There is no ability to do such with OEM remote for Pit stop. You could set up if the RS has the ability some do some don't with a Hidden switch. Again like a one wire setup. Press the switch it is like getting info from the RS remote. There is things that can be setup to act as a fail safe. So the kids are not starting your car if you leave them in the car lol

About your RS that was far away it was with the aftermarket fob. What I am talking about is your OEM. Sadly it is very limited compared to the aftermarket. I am sure your OEM may have worked from that far. One because it was DLOS. If you were that far with your oem though a few buildings or even in the back part of an office that has a few walls between you and the car. More likely the car wouldn't get the OEM and depending on the aftermarket unit may have seen that one.

Now for the Seats and what not. There is good news about that. Some not all but some Aftermarket systems can take input for such items. There are ways that can be done on systems without it being an option in some cases. Again it would depend on the aftermarket setup...

Most cases and I think even if you were to look at the OEM info about range it would state something around 300 feet.

In some cases with how the computers are working now days in these cars. For a NEW 13 to 18 it maybe harder to setup Memory seats to work with aftermarket system. Mainly because the seems OEM is trying to make it harder for people to work on or understand the on board computer systems. Some times this is related to the info to turn on your seats lets say isn't done with normal means. If it is done with Data lines it would be harder to pull off... If it was 12v or ground even something by resistance value then it could be done. IF it is run over the CAN bus or even older crude data lines it would need some extra device built. That is above my pay grade..

James