Sorry to throw another wrench into things but don't you guys vehicles have the retained accessory power feature most new vehicles have these days that retains power to the accessories until the door is open or for 10 minutes after the vehicle is shut off?
I have that feature in my truck and if I remote start it and leave it until it shuts off by itself or if I turn off the car using the fob, my accessories retain power including the radio, PC and the monitor for approx. 10 minutes before shutting off. That would be a problem if I start my car from a distance and do not go to it to physically open the door. As a result that rules out the option for me to have my car start at intervals or to start it and shut it off as that 12" screen in the dash will certainly draw attention.
But a remote start would have its own power - not thru ACC ETC.
But I think Dluvr22's point is the PC/screen is switched on/off by the accessory circuit and the RS usually triggers that circuit so the PC would boot on RS and stay on 10min after the RS shuts down leaving the screen illuminated.
Depending on vehicle, some have 2 or 3 separate accessory circuits. For the RS, the main one to pickup is for the HVAC (the main reason for having a RS). If your vehicle has a second or 3rd ACC circuit, you could connect it to the RS and trigger your PC off of that circuit (or just the monitor if you want the PC to start on RS).
Just a small thought.
Depending on the vehicle, you may have an alarm bypass module and/or a key fob transponder bypass module with a code being generated for the vehicle CPU security system. Most have an output that can be used to indicate a remote start operation.
If not, there’s usually an Ignition key detect line, use this to enable a tiny relay for screen/PC start-up. They should only run if the key is in the IGN and not if remote started.
I know this is an older thread but I just came across it so I'll throw in my $.02.
To answer the "has anybody done it?" question, yes, I have. It's not something that I set out to do, it's just a feature of the alarm I have that worked out so I could do this. The alarm is a Clifford AvantGuard 4. Clifford (this is pre DEI) used a PC interface on it's IQ line of alarms and remote starters for programing features. In the software you have the ability to test the different alarm outputs including remote start.
So the next question is "how do you use it?" The only time it was of any real use to me was when I'd be working on the carputer while at my desk using a remote connection. If I noticed the battery voltage was getting low I could just start the engine and let it run for a while. There's definitely more potential with this setup, but I haven’t been able to get the computer to connect to the alarm since upgrading to Windows 7.
Like PhilG suggested, if you have a separate accessory output from the key cylinder for HV/AC you can disconnect the wire from the remote start that is powering the other accessories. On most newer vehicles there is only one accessory wire and everything is turned on by the BCM. I placed a normally open relay on the power wire for my monitor and another on the remote turn on wire for my amp. Between the ignition cylinder and where the remote start's accessory wire connects to the vehicle's accessory wire I placed a diode. I then connected a wire to turn on my relays between the ignition switch and the diode. When I remote start, the computer will start but the monitor and amp don't turn on until I turn on the key.
This is good to hear. Hopefully you're still around later in the year or early next year when I have time to give this focus.
I did not read the ENTIRE thread, so it may have been covered. But my take on this is:
Starting a car outside of traditional method (key/crank) is difficult these days. It pays to buy a remote start unit. There are ways (that I have not done) to trigger a remote start box beside using a remote.
You still need a low-power way to wake the computer and then trigger the remote start.