Thread: Starting carputer with keyless entry

Probably not possible with a factory remote-entry...
You could make a latch-relay, hooked up to the dome light, but then how do you unlatch it when you leave the car??

Here's the wiring diagram I had in mind.



This way the power supply would receive a signal to power up when either the keyless entry box turns on the dome light, or the key is turned to the "ignition" position.

I believe I'd need some diodes where I drew the arrows, though, so that the dome light doesn't stay on all of the time, right?

Okay, I see what your saying now...
But if you don't get in the car and start it before the dome goes off, then your PC will shut off...you probably already knew that
Your right with both diodes...go big, just to be sure...3A or so

Originally Posted by WuNgUn

Okay, I see what your saying now...
But if you don't get in the car and start it before the dome goes off, then your PC will shut off...you probably already knew that
Your right with both diodes...go big, just to be sure...3A or so

Thanks for the confirmation on the diodes. I figured I'd just set the "back to idle state" delay such that even if the dome light shut off, I'd have enough time to start the car - I believe I can set a 20/40/60 minute delay time.

The only problem I see is, usually when you shut off a car, the dome comes on as well, so when you leave your car, you won't be there to see the PC shut down...
And if it hangs, that an extra 20/40/60 minutes of battery drain...

The easiest thing to do is to upgrade you keyless entry to a better one that has a remote starter built in. That way you start the car, the PC turns on and not only is the PC on but you just get in and drive away. They are so cheap nowadays.

Or you could wire it up similar, with diodes of coure, to the unluck button, that way the unlock would trigger it, and not the dome light, so that you didn't have the pc turning back on when you opened your doors to get out.

Good suggestion HiJack...
Remote starters are pretty cheap these days too.

Originally Posted by HiJackZX1

The easiest thing to do is to upgrade you keyless entry to a better one that has a remote starter built in. That way you start the car, the PC turns on and not only is the PC on but you just get in and drive away. They are so cheap nowadays.

This isn't an option for me. My car has a manual transmission and using a remote starter would mean bypassing the clutch switch and leaving the car out of gear, which I'm not willing to do. A failed e-brake cable could leave me with a totaled car, I've seen it happen.

Originally Posted by punker248

Or you could wire it up similar, with diodes of course, to the unlock button, that way the unlock would trigger it, and not the dome light, so that you didn't have the pc turning back on when you opened your doors to get out.

I like this idea, but it would definitely require a shutdown delay. I could just wire up an additional button to the shutdown jumpers and hit that as I get out of my car. That way I wouldn't have to worry about the 20 minute battery drain.

Am I correct in assuming the power supply is smart enough to know whether or not the computer is currently on? If not, if I were to manually pulse the computer to shut off, then 20 minutes later the power supply blindly sends the computer another pulse, it would turn the computer back on. Is this the case?