Hey all,

I'm currently toying with the idea of adding a remote start system to my car. Even better, it will use the factory fob. If you're interested in what I'm thinking about doing, read on (warning, longish post)!

Now, when most people think of a remote starter, they think of either a factory system, which is very integrated with the factory computer, or an aftermarket system which typically relies on expensive and excessively complicated and sensitive alarms and usually costs hundreds or thousands of dollars depending on the car. For a Corvette, I hear the process is quite involved.

This is not what I am planning. My idea will cost me under $100, and only a couple of hours of actual installation.

What I am planning to add is:


the necessary relays and other small electrical components

The principle behind what I'm going to do is:
1. The 1101T unit houses a factory key fob with the battery removed. Instead, it comes with wiring that replaces the battery and switches the fob on/off whenever necessary. This means that the factory computer has no idea that the fob is in the car whenever the unit is off. Whenever the remote start is triggered, the 1101T supplies power to the key fob, and the car recognizes that a fob is now present within the car.

2. The 4003L unit is designed to be connected to a source which receives a pulse whenever the lock button on the fob is pressed. If the lock button is pressed 3 times, the remote start sequence is then activated. Given that this car doesn't have any mechanical locks and all locking is done within the BCM, that will likely be difficult or at least annoying.

3. What I am planning, however, is to tie into the horn circuit, so that if I press the lock button 4 times in quick succession, the horn will honk 3 times (once each on the second, third, and fourth presses). This adds one additional button press, which should decrease the likelihood of accidental activation. The only problem with this approach is the possibility of the system being activated just by me honking the horn 3 times (although I may be able to bypass this situation through some careful wiring or with some relays). I may not go this route, but if not then I would have to closely examine the wiring to find a source of a locking pulse.

4. Once the remote start sequence has begun, the remote start unit will close a relay (or relays) that will simulate the pressing of the start button and the pressing of the brake. After a second or so, this relay will re-open. The car will remain locked. This isn't particularly hard to do. I've studied the wiring diagram for the starter switch, and I will likely be testing this portion of the system within the next couple of days.

That's the main difference between my idea and a typical remote start system. For most cars, the remote starter only starts the engine and turns on the AC or some other group of accessories. You still have to put in your key and turn the rest of the vehicle "on" and such. This system forgoes that route for one that truly simulates the driver physically pressing the start switch and brake pedal.

This is a relatively simple setup. Because of this, there are a couple of potential issues, but they are mostly irrelevant.

The largest potential problem, which I'm sure a few of you are considering by now, is the possibility of someone getting in the car and driving away. Why does this not concern me? 1. The vehicle remains locked until I either walk up to it and open the door with my fob in my pocket, or press the unlock button on my fob. There's no other way to open the door. 2. The range of the remote start system is identical to the range of the fob's transmitter, which means that I can't really be more than 100 feet away on a clear day with a brand new battery. Realistic range is much smaller. Technically, I suppose someone could break my window and drive away, but I don't foresee using the system in any situation where I was concerned with this happening.

The system basically works in the same way as me walking out of my house, getting in the car, starting it, getting out, then locking the car. Just as secure/insecure as that method.

Why do I want to do this? Well, primarily, it would be nice to have the car warmed up in the morning without the pain of getting in and out of it. Yeah, I know it sounds lazy. Also, just for the "second kind of cool" factor (meaning, no, it does not offer any REAL utility, but it makes me feel good about it so it is "cool").

Eventually I could expand the system to include an Arduino or other microcontroller, which would allow me to add other activation methods through a connection to my cell phone (either text messages or a bluetooth connection). I could also add passcode locking to make sure the car can't be started without my knowledge/approval.

Thoughts? Suggestions? Comments? Concerns?

Thanks for stopping in! I'll keep this thread updated with any progress toward the project.

 

Not a deal breaker, but be aware that the purple "start" wire clips on to the starter solenoid with a Weather Pak connector (BTW a huge drag with the dip stick tube right there). Just means you will have to splice into that wire with the remote start relay rather that bolting it on like most other cars.

 

Well, I'm not actually interfacing with the starter or solenoid directly at all. Merely telling the computer that I pressed the start switch and brake, and letting it start the vehicle as normal. Doing it the usual way would require a lot more work and engineering on my part.

 

1) There is no "lock pulse" on a C6, because the doors never "locked" in the traditional sense, only a value in the BCM storing a bit whether the door can be opened. *Every* time the "door open" button is pressed, the door asks the BCM if its ok to operate. This bit is changed for more reasons than just "lock button on fob or door depressed".

2) The C6 is an electrically complex beast. Jumping a wire here and there often has complex interactions, the most common of which is the addition of the add-on jumpers and circuits preventing the car from "sleeping" and ending up with a dead battery, repeatedly.

Can it be done? Perhaps. But it may require a lot more hacking than it appears, and the more hacks done to a complex system, the more unstable it may become.

If you decide to give it a go, Keep us posted! Should be interesting from a learning perspective.

 

From your profile, it says you are an electrical engineering student, so with that in mind, this sounds like a fun project. Challenging, but rewarding once you get it done. For the average guy, it seems like a great deal of work for not much reward. What I mean is that since the C6 is usually not a car that sits outside in the snow all the time waiting to be driven, the advantage of remote start are few and far between. I have remote start on my SUV and it is a wonderful feature that I love in the winter, but if my C6 had it, it wouldn't mean much to me because of the way I drive the car. Be sure to keep us caught up on your progress...finding all the different inputs for the system will be very interesting and fun.

 

Wow, sounds cool. I would have no clue how to do that. I found this module a while back that allows you to use your factory remote as well.

http://www.crutchfield.com/p_938EVOALL/Fortin-EVO-ALL.html?tp=149

 

When the start button is pressed, it essentially sends 2 signals to the BCM. 1 is the signal from the RCDLR that tells it that a valid key fob is present in the car. This signal can just be shorted from one wire to the other - that's all the switch does.

The other signal is from the BCM, through a 1.5 KOhm resistor, and back to the BCM (interesting note: if you press the switch OFF, it runs this signal through a 300 ohm resistor).

The other 6 pins are either data pins or ground, none of which are changed or affected by pushing the switch. Because the switch will remain in the circuit, no harm SHOULD be done by jumping the necessary pins (although with my luck I'll be in the market for a new BCM soon lol).

Mainly, this is just a fun, hopefully cheap project for me to do with the car. No real practical application for me. Honestly it'll be cool to hear the car start up from the outside more often.

With regard to lock pulses, if I really felt like it, I could tap into the CAN system and read all the data off of that. Every time the lock button is pressed, a signal is sent through the CANBUS. Now, I would have to set up a micro controller to do it this way, but it's definitely doable. This is the same principle that the popular window valet operates on. A little too complex for me to work on during the semester, but perhaps a fun extension to try during the summer.

 

I am no electronic expert, so i wont question wether or not your plan will work, but having had several remote starters installed in my vehichles i don't see any advantage other than cost in your plan, i actually see a few disadvantages, for one a modern Viper system can start a vehichle almost 400 feet away, all systems will shut down a vehichle when someone enters it and presses on the brake, i don't think someone who will steal a car will think breaking a window to get in is too much of an inconvenience, and last all systems have a 10 or 15 minute time out installed to automatically shut down the car if you don't get in it and go.
I did once remotely start my truck with the intention of going to the store, i sat down on my couch and waited for the truck to warm up, well i fell asleep and woke up several hours later, so i do see the importance of a time out feature, granted that would usually not happen, but i was glad i had the timeout then, and lastly the last remote i had installed a Viper system in my truck a year ago, it was a middle of the road system, only cost me around $350.00 installed. If your doing this as a project then have fun, but i don't think you will end up with a better system than what's already out there.

 

All of these are valid points. Quite frankly, the C6 is not ideal for what I'm wanting to do. To be fair, the system I'm planning on installing supports all of the features you mentioned. The problem with the C6 is that, not only it is a vehicle that is not designed from the factory to be remote-started, it has several attributes which make it nearly impossible to install a conventional remote start system on (unless I'm missing some key detail here).

So, if you want a timeout on the remote start, you have to have some circuitry in place that tells the remote starter that you've gotten in the car with your fob, so it's okay for the car to run indefinitely. This is almost impossible to implement on the C6, unless you tap into the CAN system and wait for a signal from the RCDLR that says that a good fob has entered the car. Possible? yes. Worth the time for me? no.

The same idea applies to the brake shutdown feature, which is typically designed to shut down the vehicle if anyone steps on the brake unless they turn the ignition to "on" before this. The problem is, there is no conventional ignition switch in the C6. The start button is really just an "engine start request" button, which tells the BCM that the driver wishes to start/stop the engine or put the car in accessory power mode. It would be possible to somehow use the switch to tell the remote starter that you got in the car and pressed the start button, so it's okay for it to disable the brake shutdown, but you would still have to check with the RCDLR and make sure that there is a good fob in the car.

The real problem is that if you go down the list of required inputs for any remote start system (eg. lock pulse, various ignition wires, etc.), the C6 doesn't really have any of them. In most vehicles, all the necessary information is available from a multitude of wires that you can tap into. In the C6, nearly everything is transmitted between various modules in the car as serial data using the CANBUS/GMLAN network.

Could I, if I really sat down with a ton of time on my hands, the wiring diagrams, and a full list of GM communication protocols, design a system that would basically plug into the OBDII port and work as a plug-and-play remote start system with no splicing or setup of any kind, that would support all the security features of traditional remote starters? Probably. I don't anticipate ever having that kind of time though.

I mostly think my idea is 1. a fun project that will take me a weekend without any real programming involved, and 2. a good starting point that I can add other features to.

I'm very fortunate in that I live in an area where I am not concerned for the security of my vehicle. If I am ever somewhere sketchy, I highly doubt I would use a remote start system anyway, even if it had a foolproof security system. Starting a loud, flashy car draws attention, and if you still have to walk 400 feet to get to it and it's not in your line of sight, there's a good chance that a less-than-scrupulous character could have the opportunity to wait for you by your started vehicle.

You can add security to any system, even to the point where the security becomes an inconvenience, and more often than not that added security will not really stop someone who wants what you have if you're not already practicing basic/common sense security principles. For most common crooks, having the door locked is enough to prevent them from messing with a car any further, locked or not.

I know there are exceptions to this, but I'm confident that I'll be covered adequately. I plan on putting a remote-start-disable switch in the car so that if I loan it to someone or I'm somewhere sketchy the remote start won't accidentally be triggered.

Sorry if I came off as confrontational at all; it wasn't my intention at all. Haven't slept in a while so yeah...

 

Don't be sorry , you didn't come off confrontational at all, as i said i am no electronics expert and it sounds like a great project, have fun with it !