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Hardware Hacking Transportation Build

The DIY $10 Prepaid Cellphone Remote Car Starter 454

An anonymous reader writes "Wish you could start your car via your cell phone, but don't feel like ponying up the $40k for a Chevrolet Volt or $499 (plus $29 a year) for an aftermarket system from Viper? This hack relies on a cheap prepaid cellphone that has had its vibration motor surgically removed, replaced by a couple of leads triggering the car's starter. Whenever the phone receives a call it starts up the car — a somewhat dodgy proposition if a telemarketer ever gets hold of your number, but an interesting solution nonetheless. Total cost of the project: $71.03."
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The DIY $10 Prepaid Cellphone Remote Car Starter

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  • by janek78 ( 861508 ) on Monday January 25, 2010 @10:55AM (#30889996) Homepage

    On many phones you can group contacts and assign different ringing profiles. You could just program in allowed numbers and set all other calls to "silent".

    I personally leave my car in gear (with the reverse locked in if I leave it for extended periods of time), so this would not be very practical. :)

  • by sunderland56 ( 621843 ) on Monday January 25, 2010 @11:26AM (#30890482)
    There are some tasks that machines are bad at; gear selection in an automobile is one of them. Automatic transmissions cannot predict when you are approaching a curve, or a hill, or other vehicles. Gear selection needs to be based on what you are about to do, not what you just did.

    Note that all race cars use manual transmissions, as does any decent sports car, for just these reasons.

    Automatic transmissions are also mechanically inefficient. Cars with a manual gearbox generally get 1 or 2 more miles per gallon; it is strange how many people want an efficient car, yet they elect to pay extra for the automatic option.
  • by rnelsonee ( 98732 ) on Monday January 25, 2010 @11:28AM (#30890526)

    In modern cars, I keep hearing that warming up your car isn't needed, and can actually be bad for it []. Note it still recommends 30-60s to let the fluids warm up, which makes sense.

  • by name_already_taken ( 540581 ) on Monday January 25, 2010 @11:31AM (#30890568)

    What happen's if someone finds out your phone number? Can they steal your car?


    This is just using a cell phone to trigger the auxiliary trigger input on a remote starter system installed in the car. Basically this input just simulates pressing the Start button on the remote starter's remote.

    Installed correctly, most remote starter systems will stop the engine if the brake pedal is pressed. Additionally, since the ignition key is not in, the steering is locked. Also, if the engine speed goes over a certain limit, the remote starter will stop the engine. Most cars with automatic transmissions require you to press the brake pedal to shift out of Park these days, so there's no chance of stealing the car that way.

    I suppose if the car had a manual transmission, it would be possible to make it move forwards or backwards in whatever direction the steering wheel is pointed, but only at slightly over idle speed. You might be able to drive it up onto a trailer.

    The problem that might come up is that most of these systems come with a pin switch that disables the system if the car's hood is opened (so you don't get your hands torn off when the engine starts unexpectedly, while changing a belt for example). Many people do not bother to install the hood pin switch. You would want to make sure it is in place and working, because a telemarketer's call could be deadly.

    If the phone rings while you're driving or the car is already running, nothing happens other than the remote start will keep the engine running after you remove the key (if you don't touch the brake pedal.

  • by Anonymous Coward on Monday January 25, 2010 @11:33AM (#30890618)

    Ever start your car in temperatures below -40? And that's not counting wind chill. Your engine will not like it if you jump in, start and go with zero warm up time. That being said, 30 seconds to 2 minutes is all the time needed to get the juices flowing.

  • Re:Phone cost (Score:3, Informative)

    by mcgrew ( 92797 ) * on Monday January 25, 2010 @11:34AM (#30890628) Homepage Journal

    Your numbers are WAY off for Net10 and TracFone. TracFone's minutes are three times what Net10's are; I've used both. Net10 would be a good bet; you would only need to buy minutes if your card ran out, which iirc is about once a year. So you're talking thirty bucks a year -- you don't spend minutes if the phone isn't answered, and it wouldn't need to answer to start the car.

  • by jridley ( 9305 ) on Monday January 25, 2010 @11:38AM (#30890690)

    I prefer manual transmissions myself, but automatic transmissions these days are not all that bad. You give up maybe 1 MPG usually, and even then it depends on if your A/C is on. With the A/C on a car with automatic may actually be a little more efficient, because it's programmed to cut the A/C off during heavy acceleration. This is especially helpful in city driving.

  • Re:Phone cost (Score:3, Informative)

    by Pretzalzz ( 577309 ) on Monday January 25, 2010 @11:41AM (#30890736)

    T-mobile's minimum is $40 a year[$10 every 90 days], or $100 for the first year and then $10 for subsequent years.

  • Re:Why? (Score:3, Informative)

    by codepunk ( 167897 ) on Monday January 25, 2010 @11:43AM (#30890790)

    Outside temperature 20 below zero, think about it. Some areas of the US have very harsh winters, remotely starting
    a car 10 minutes early remotely allows time to warm the interior to something more comfortable say 40 deg. Not
    to mention it is better for the engine to be at least slightly warmed up before placing it under a load.

  • by Lumpy ( 12016 ) on Monday January 25, 2010 @11:46AM (#30890842) Homepage

    Um no, not unless you are looking at racing from 10 years ago or longer. Automatic transmissions DOMINATE drag racing right now. you get spooky consistant ET's running an Auto, plus you can get Auto transmission that handle far more HP than manuals.

    Also some of the more recent rallies in europe are being won with automatics in the car.

  • by karnal ( 22275 ) on Monday January 25, 2010 @11:47AM (#30890868)

    Manuals will cut the AC off under heavy load as well. Had two Chevy vehicles that you could tell would kick the AC off under load or high RPMs and they were both stick.

  • by Sigmon ( 323109 ) on Monday January 25, 2010 @11:58AM (#30891028) Homepage

    SNOW is not generally a problem when it comes to defrosting windows... it's ICE. Keep in mind, some of us live where much of the frozen perciptiation we get is not like the nice fluffy and powdery snow you may get. It's a totally different ball-game when there's a layer of ice on your windshield twice as thick as the glass itself. Sometimes you have to let the engine warm up enough to melt the undersurface before it can be scraped off.

  • by GSMacLean ( 1333075 ) on Monday January 25, 2010 @12:01PM (#30891080)
    You have no idea what you're talking about. Pretty well every gasoline engine has the capability (and the provision) for the addition of a block heater. Go up north where -40 is a normal winter temperature, you'll see everyone has block heaters. Even store parking lots have lines of plugs for you to plug your car in while you go inside. By the way, the only reason Diesel is more expensive here (unlike the rest of the world, where it is cheaper - which make sense, because it is far less refined and less costly to manufacture than gasoline) is because the government heaps taxes on it.
  • by BassMan449 ( 1356143 ) on Monday January 25, 2010 @12:11PM (#30891288)
    Mod this up. I live in the US Midwest and snow is not a problem, but we tend to get ice at least once a year. Even if the ice is only a quarter inch thick, you can't scrape it off (at least not without breaking your scraper) until you warm up the car a little to loosen up the ice. Snow is very easy to deal with and my car has my window defogged in 30 seconds but getting rid of the ice takes time.
  • by PhotoJim ( 813785 ) < minus poet> on Monday January 25, 2010 @12:25PM (#30891598) Homepage

    The problem is that most people crank their defroster to maximum fan speed and that makes the engine take forever to warm up . The secret is to put the fan on a low speed (even 1) and don't be in the car for a minute or so (while you clear the windows), then ease it up to 2 and start going. Notch the fan up as you notice your temp gauge going up. Don't use maximum speed unless your engine is at full operating temperature. Even then, very small engines in very cold weather will lose heat at maximum fan speed unless they're actually driving (i.e. the engine is under load); idling at full fan speed may still result in the engine cooling off.

    I start my engine, leave the fan on low, turn on my seat warmer, clear the windows, and by the time the windows are scraped, I drive. Drive gently and easily until the engine is warmer. That way I get heat quickly and I am friendlier to the environment.

    If the interior of your car is really humid and you're getting frost inside on the windows, turn on the air conditioning. This will help to sublimate the ice faster. (Keep the heat turned to the warmest temperature, of course. It'll still warm up your car - but with air with less humidity in it, which helps to remove the frost and ice.)

  • by Anonymous Coward on Monday January 25, 2010 @12:33PM (#30891738)

    Washington, D.C. is only barely behind []) L.A. butI still commute here with my manual transmission. At 75K mi my clutch disc still grabs like an acrophobe on top of a bungy platform.

    Knowing how to operate a manual transmission mechanism is only one part of knowing how to drive. To properly drive a manual transmission vehicle in heavy stop-and-go traffic you cannot tailgate and you will spend a lot of time in Neutral. Yes, this means that more than once per-commute someone will cut in front of you because there was more than 5 feet between you and the vehicle in front of you even though your "performance type car" could have avoided that by hanging 6 inches off the rear bumper instead.

  • by fprintf ( 82740 ) on Monday January 25, 2010 @12:47PM (#30891976) Journal

    How about a citation? "Every" automotive expert? I have lived in a cold climate several times in my life, and currently live in a moderate climate where temps are usually below freezing all winter but not below 0 degrees F. In addition to that, several family members are certified mechanics or mechanical (automotive) engineers. With a properly chosen motor oil, there is no reason that a modern automobile cannot be started and driven away within seconds of turning the engine on. In addition, I have experience with the 2-cycle and 4-cycle snowmobile industry and the factory recommendations on those high performance motors is that they can be driven away immediately upon starting a cold engine.

    Tappet Bros. and Consumer Reports are correct.

    You are correct that startup from cold is the most damaging time for a motor. However it is not less damaging to let it warm up before driving it, as long as a) the oil is the correct viscosity for the temperatures and b) the driver does not accelerate too rapidly.

  • Re:A thought occurrs (Score:3, Informative)

    by natehoy ( 1608657 ) on Monday January 25, 2010 @01:20PM (#30892588) Journal

    Not if they used the remote start circuitry in the car, which it looks like this author did. The remote start circuit already has all the safety features built into the regular ignition key starter, plus probably a few extras.

  • by 0100010001010011 ( 652467 ) on Monday January 25, 2010 @01:24PM (#30892644) [] [] [] [] [] []

    I've heard them a few times give quite a bit of misinformation. They haven't the slightest clue about the differences between WVO, SVO, BioDiesel. Say that 10,000 mile oil changes are 'stupid' (It's VW recommended, they go up to 30,000 km in Europe).

  • Better design (Score:5, Informative)

    by Animats ( 122034 ) on Monday January 25, 2010 @01:45PM (#30892910) Homepage

    Here's a better solution. [] This design connects to the cell phone audio output (so you don't have to open the phone) and has a DTMF decoder chip, so you send it tones to make things happen. That at least gives you some protection against random phone calls.

  • Re:Why? (Score:3, Informative)

    by Monkeedude1212 ( 1560403 ) on Monday January 25, 2010 @02:09PM (#30893224) Journal

    Like the other poster, you obviously have not owned a car where the temperatures drop REALLY low.

    Where I live, when it reaches minus 40, it will take 15 minutes of my car sitting in Idle for it to become DRIVEABLE - let alone the 20 to 30 before it would actually become a comfortable temperature. If I don't let it idle for that amount of time, it will stall about as soon as I try to put it into any gear. The gas line needs time to get the gasline antifreeze flowing - the oil needs time to warm up and get inside the cylinders (this is were plugging in your car is helpful).

    You run the risk of harming your engine by driving before the oil has time to warm up and flow around. Nothing like a Seized engine because you didn't let your car warm up 10 minutes every morning.

    Here in Canada - and some Northern States, a lot of countries in Europe, and probably Russia - Remote Car starters are a BIG thing.

    However, its only like $120 dollars to get one done here for an automatic, and about $150 for a standard.

  • by natehoy ( 1608657 ) on Monday January 25, 2010 @02:12PM (#30893264) Journal

    The Volt comes with an iPhone app that allows you to start it remotely over the mobile phone network.

  • Re:Why? (Score:2, Informative)

    by Nos. ( 179609 ) <{andrew} {at} {}> on Monday January 25, 2010 @02:26PM (#30893478) Homepage

    Might want to get your car looked at, tuned up, or replaced.

    This winter, I've driven three different vehicles several times in -30C and below. All of them required a minute tops to be driveable. During that time I'm generally clearing snow off the vehicles (including the roof and hood). In 20 years of driving in Saskatchewan, I've had very few cars that acted any differently. The ones that did were old beaters that probably shouldn't have been on the road.

    If you feel the need to wait until your interior is toasty before driving, then by a timer and an interior car warmer. Way more efficient and easier on your car. That or learn to dress for the season. I can get in a cold (-30C) vehicle with my jacket, insulated shoes, toque and gloves and be very comfortable in the car. In about minutes of driving the car is pumping out enough heat that I have to turn it down.

    If you're gas line is freezing up, keep more gas in the tank, more gas = less room for humid air.

    Use a proper viscosity oil for the season. No reason the oil shouldn't be at a reasonably temperature within a minute, even if the ambient temperature is -35C.

  • Oh, jebus (Score:3, Informative)

    by sean.peters ( 568334 ) on Monday January 25, 2010 @02:40PM (#30893686) Homepage

    Dude, it's not that hard. 1) start car, turn on defroster. 2) Scrape windshield. 3) by the time you're done, the inside of the windshield is already defogged, even if the defrost hasn't gotten up to temperature yet. It doesn't need to be warm to get the fog off the inside of the windshield, it just needs a few seconds of relatively dry air blowing over it... which you get from the first few seconds of defroster. It only needs to get warm at all to get the frost off the outside of the window, which, you know, you already scraped off.

    I can't even believe we're having this discussion. The idea that not preheating your windshield inevitably means that it's impossible to see is mind-boggling.

  • by lowrydr310 ( 830514 ) on Monday January 25, 2010 @03:37PM (#30894408)

    Automatic transmissions cannot predict when you are approaching a curve, or a hill, or other vehicles. Gear selection needs to be based on what you are about to do, not what you just did.

    Have you driven any modern automatics recently? They've come a long way since the 80s and 90s. They have all sorts of sensors that measure engine load, accelerator position, and vehicle grade and they're much more effective at keeping or putting the vehicle in the proper gear for the task.

    I'll have to admit it's not as 'perfect' as I would be controlling a manual gearbox, however 99% of the time it's very effective, and a minor sacrifice for the convenience of not having to shift.

    Also the fuel economy isn't always worse on the automatics. Some autos actually do better than their manual brothers.

    In the case of the BMW 335d, there is no manual transmission available because they don't make one that can handle the massive amount of torque produced by that engine.

    Now despite all the defense I just made for the automatic, my personal preference is for a manual transmission. Unfortunately my vehicles are shared with someone else, and she doesn't like shifting.

Machines that have broken down will work perfectly when the repairman arrives.