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abecedarian

Vehicle anti-theft / RFID fob.

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As a note, if you drive a manual transmission car you will not lose power steering if the engine shuts off, unless you take it out of gear or put the clutch in. The same goes for power brakes.

 

Automatic transmission cars you may or may not lose both, depending on how well the torque converter freewheels.

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I just bought a new car but in the Durango I had an IR setup that kept watch over the car. Lights only go on in the car when the doors are opened. In the driver's wheel well of the car I had a simple oscillator connected to an IR led pointed towards my bedroom window that only got power when the lights in the car came on.

 

At my window, I had an IR photodiode that fed an amplifier. Switch it on when I go to bed at night and I know when someone is in my car :) It'd pop when the motion light came on and would go off if the door was opened. Simple, but effective(at night at least).

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Interesting idea. The system could engage the starter and sample the IGf pulses ("I Got fire"), and when the pulses were occuring fast enough for it to assume the engine is running, say something like 33 pulses per second, disengage the starter. 33 pulses per second would equate to approximately 500 rpms for a 4 cylinder engine: 33 / 4 * 60 = 495. 495 is greater than the cranking speed, but slower than idle so should be a good indicator the engine is running and doesn't require the starter- far better, in my opinion, than just holding the starter for 5 seconds or something like that.

 

But I'd still need the key in the ignition switch to unlock the steering wheel and gear selector.

 

The more I think about this, the best place to locate the module would be within the ECU itself. I wonder if there's room?

 

This is how remote starters know they are working. You piggyback an injector wire , usually <5v signal line. You could piggyback any number of systems , such as fuel pump , injectors , or even take straight crank/cam signals. The last is risky , as loss of either will result in CEL and/or shutdown. On some cars (dodges come to mind) , even a slight alteration in the waveform will cause rough running , or shutdown. Even some aftermarket sensors require the control modules to be re-programmed with the new waveform to run well..

 

The starter is never used as an indicator , because you may crank for hours and not be running. The starter is almost always only used as an interrupt point.

 

 

As a note, if you drive a manual transmission car you will not lose power steering if the engine shuts off, unless you take it out of gear or put the clutch in. The same goes for power brakes.

 

Automatic transmission cars you may or may not lose both, depending on how well the torque converter freewheels.

 

This is incorrect in 90% of the situations. Unless you have an older (pre-power steering) car , or a vehicle with a low enough gear ration (or power-assist) , then you will absolutely lose power steering and brakes. You will be able to steer and brake , but not with the hydraulic assist that you have when the engine is running. The power steering is ran from a mechanical fluid pump usually (again , exceptions are rare) , and the brakes are ran from vacuum assisted hydraulic master cylinder. This is why your brakes dont work great when your car dies. The vacuum pulls the master cylinder diaphram which you push (through linkage) with the pedal.

 

KyleJ has a great idea, other than the fact that your photodiode setup doesnt travel with you. This would work great at home , but the second you move out of range , you are no longer protected.

 

 

If I was you , I would put a redundant failsafe system in , that can easily be bypassed if you know how. This would be a remote located fuel pump relay that could easily be controlled by a transmitter/reciever hooked/controlled by an MSP board. That would be phase one. I would also put in a physical kill switch (battery) hidden somewhere inconspicuous ( perhaps hidden above the glove-box door) , and a secondary starter interrupt that would be controlled by the lighting switch... No light , no start. If you buy a car with auto-headlights then this could be an issue , but we could work you around that simply enough (tie into the brake lights or my personal fave , dome lights.) Thieves usually like the cover of darkness , and if you setup your starter interrupt to run when dome lights are on , then you would have around 10 seconds once you get in the car to start it.

 

If you have a remote unlock key fob , this could still work from a distance , as when you unlock cars from the fob , they turn on the dome lights. Also , you could tap into the headlights if they flash when you unlock , and use that to wake up the MSP.

 

 

what kind of car or truck are you lookin at?

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edit-

 

forgot to mention , that you could tie into the driver door ajar switch (electronically or mechanically) to wake up. It all just depends on what you get. You're on the right track though.

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IR photodiode link to the bedroom window is a no-go: can't see the driveway from any window.

 

The torque converter will turn the engine to turn over at ~10 mph road speed, so I know it won't lose power steering and vacuum assisted brakes at relatively low speeds; I know 'cause I've tried it.

 

I really do appreciate the feedback on this, but much of the information I'm being offered is either irrelevant to my truck, or is coming from someone who didn't read the thread before replying.

 

It's a 1991 Toyota pickup (HiLux in some markets). It is a 2wd 22RE 4 cylinder / automatic (basic 3 speed with torque converter lock-up for over-drive), so no fancy solenoids or speed sensors to worry about: just a simple detent cable from the trans to the throttle body as most older automatic transmissions have, and that's about it. The relative simplicity of the system I have (pre OBD-II), as well as my familiarity with the 22RE itself (Google or Bing "abecedarian" and "22re" and I'm right there at the top of the results- that should tell you I know what I'm talking about with reference to my trucks), is part and parcel to why I was thinking, initially, an RFID key fob would suffice, in some way, for security.

 

Please do not think I am a total idiot.... I'm just an idiot with respect to MSP430's and RFID. I have been my own mechanic for nearly 30 years... and I'm only 42.

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i do not in any way think you're an idiot. I am familliar with the hilux , as well as the 22r and 22re. I drove and 88 ir 89 hilux with the same 22re but standard trans.

 

Fortunate for you , the truck has rack and pinion. If you do not have to put in some extra effort (when sitting still) to turn it , while off , then you have issues. When rolling , every car is much easier to steer. Pre 96 would have had a larger master cylinder , and iirc , relied less on the vacuum assist for brakes. You never specified what truck/car you had , so thats why I gave options. I was under the impression you were going with something newer.

 

And just like bobnova said. Depending on your torque converter (TC clutch) , your motor may or may not continue to turn. Rarely do I work on anything pre94 at this point , and when I do , its usually 30's , 40's , or custom (off road buggies , etc)

 

 

Again , I too am new with the MSP field , but where I can help someone , I try. If you would have said what you were trying to install it on , I could have narrowed a lot of the information down. My reccomendation would still be a starter interrupt , and possibly a battery interrupt relay if you're really concerned.

 

:thumbsup:

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I'm sorry but I thought the posts made said it's a 1991 2wd Toyota pickup, extended cab, steering column shift automatic transmission (3 speed + lockup torque converter), 22RE, no air conditioning.

It also has a Fabtech 3.5" lift on it, with ~30" tires... as if that matters.

 

It does not have rack and pinion type steering- none of the "consumer" Toyota trucks had that until the Tacoma was introduced late 94 and they went to "struts" for the front suspension.

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Thats odd. All of the service information I pulled up , showed it as having a rack , not a steering gear. If you have a steering gear , then that is the reason you still have power steering when your engine is off. That , and it's a small , light truck. (minus the 75# tires).

 

Pretty much at that point , your best best would be to use one msp for starter interrupt , and get yourself one with a gps reciever that you could setup some failsafes (directly from battery) that you could locate/disable the car from a remote location via gps.

 

It may not be a new truck , but a man's truck is his truck. 'Specially if he took the time to lift it.

 

 

 

As a side note , when are you going to put a secondary transfer case in it? You dont go 30" and not rock that mofo up and down a coast...

 

-hov

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All the Toyota pickups from the '70's up through at least 95 had traditional worm and idler type steering, with relay rod and such. The 94.5 Tacoma, and maybe the same year T100 (Tundra) and newer as well were rack and pinion.

 

Overall, no worries. You can search yotatech.com (use the same username if your concerned) and you'll likely find well over 10K posts attributed to me, of which I may say half are humorous and worthy of no attention. ;) ... just in case you worry about my knowledge of my truck.

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Thats odd. All of the service information I pulled up , showed it as having a rack , not a steering gear. If you have a steering gear , then that is the reason you still have power steering when your engine is off. That , and it's a small , light truck. (minus the 75# tires).

 

Pretty much at that point , your best best would be to use one msp for starter interrupt , and get yourself one with a gps reciever that you could setup some failsafes (directly from battery) that you could locate/disable the car from a remote location via gps.

 

It may not be a new truck , but a man's truck is his truck. 'Specially if he took the time to lift it.

 

 

 

As a side note , when are you going to put a secondary transfer case in it? You dont go 30" and not rock that mofo up and down a coast...

 

-hov

It has to be 4wd before I can put in a primary transfer case, and then I might consider a crawl box.... ;)

 

Just sayin.....

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Having said that, the wife takes pride in parking next to any 2wd yota, her's being more than a few inches taller.

 

2 more inches, and it would be about the same height as the 4wd.

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I thought I had seen your name somewhere else. Do you have any other hobbies (fly fish or bowyer) that you may have been on another forum? It may have been YT that I saw you though...

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but what people dont understand , is that its not body height , its axle to ground clearance.

 

 

 

and i have seen 2wd crawlers. . .

There's a little more than that involved. Some activities like rock crawling require better approach / departure angles and frame-to-ground distance as well as low center-of-gravity, and axle clearance may not take as large a consideration depending on the actual terrain. Others like mud bogging needs the axle-ground clearance. There are some with the mindset that just a body lift is enough for larger tires, which is true if one needs to keep the COG low, but overall, build it how you need it and take a trip. We lifted the 91 because I couldn't pass on a brand-new fabtech 2wd kit for $400 US, and then it needed larger tires to fill the wells- 30" is the biggest we could get without it rubbing the fender liners when turning so any larger tires would mean a body lift is needed, or new spindles and top mount the springs on the rear axle... and then probably have to lengthen the drive shaft and re-gear... or maybe all of the above and I figure we should be good for 37" at least. :grin:

 

I thought I had seen your name somewhere else. Do you have any other hobbies (fly fish or bowyer) that you may have been on another forum? It may have been YT that I saw you though...

No other significant hobbies of note. Here, stellarsiti, yotatech and cx500forum are my primary hangouts, though I do have an occasional presence on a few others- neowin, abovetopsecret and pirate4x4.

 

But I digress. ;-)

 

Still mulling over what I'm going to do.

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ahhh , it must have been pirate4x4. I am a long time lurker. I own a 97 zj grand cherokee , soon to get the 3.5" arms i have sitting here , with some rs4000's , and custom 4" springs. I too am trying to stay away from SYE , trackbar relocation , and driveshaft issues.

 

And of course , as you know , there are finer points to crawling , but all the lift, and articulation in the world is nothing if you grind your punkin on a curb... i have seen 2wd crawlers , but they were mostly rock. I'm in ohio , and around here everything turns to mud. I dont dig the mudding style , but I like to get my heep dirty every chance I get

 

And we are pretty close on some things ... my project work truck is a gmc sonoma that will be getting a 6cyl turbo diesel , mid mount (in the bed) , hardtail rear , direct tranny to rear end connection , along with chopping the roof , and shortening the bed as much as possible. I even thought of going convertible , but that would mean it would be a sunny-weather only truck...

 

I <3 drift...

 

-hov

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