Last time i heard two intersting myths. I am asking you to confirm them, if they are true.

1. myth:
You are stuck in trafic jam on wery hot day in old car (10 years old or more). there is a danger that your car engine can overheat. What to do. Turn your wentilation on maximum and Hot on maximum. Of course you must open all windows, or you would overheat yourself.

2. myth:
Your car can lock/unlock by remote-control. What to do if your keeys get lockd inside a car.If you have a reserve key at home, call somebody at home with cellphone (to another cellphone). Get your phone close to carlock and person at home can open door with reserve key trough phone.

Are these myth true? Please if somebody explain.

1. Is true.

2. We've discussed this elsewhere. Car remote keys do not work by sound but by some other means Infrared or radio.

Keys work by radio, the phone would not be able to transmit that on it's carrier - so No.2 could not possibly work, also even if a particular remote central locking system did use ultrasonic signals, the phones circuitry would not be able to send the signal either - they're limited to use only voiceband (300Hz - 3000Hz), the ultrasonics would be filtered out.

if you seen top gear jeramy clarkson was using a car fob at its maximum distance it worked but then he went ten feet back it didnt work so he put it to the side of his temple and it worked how the hell did this work he doesnt have a clue but its clear that your eyes amplify the signal in some way

Don't believe everything you see on TV. However I'd like to get a definitive end to this one.

The overheating thing is true - since your car's heaters work by exchanging heat from the engine cooling system into the ventilation system by means of what amounts to being a small radiator, this will help slow down heat build-up in the engine and may help prevent it overheating.

The remote control thing, however, may possibly work on a few older cars with remote controls, but I doubt it. Most remote controllers on cars these days use radio transmissions, so can not be transmitted over 'phone lines. A very few cars, particularly earlier Renault "plip" remotes use infra-red signals. (You may recall the dark plastic receiver "lens" used to be mounted under the rear-view mirror.) Renault switched to radio signals, supposedly after a spate of car thefts in France, where car thieves reportedly used "learning" type multi TV remotes - as people locked their cars in a car-park, the thief would be nearby, pointing his TV remote at the driver's remote and "copying" the signal, then using it to open the car after the driver had gone. Good story, but absolutely no idea if it's true. Obviously, IR won't go over the phone!

I do know that some of the very early remote car alarms used an ultrasonic remote signal, similar to some of the early remotes for T's and VCR's. At least one car-theft ring, operating in the Southampton & Bournemouth area was known to be carrying high-end recording equipment and directional microphones to "copy" these signals and then "boost" the cars. Theoretically, I guess, if you had one of these systems you could pass the signal over the phone - but I'm not at all sure that any telephone has good enough sound quality to transmit an ultrasound signal successfully, and there surely can't be many of these systems left, they were only around for a few years in the 80's.

I've heard a few stories of enterprising thieves "recording" the radio signal from remotes and playing them back to open cars, but that would also be impossible nowadays, since all manufacturers use a pattern or sequence of codes in their remotes, which changes every time you "fire" it. For example, if you own a Vauxhall with a remote locking facility, don't let your kids play with the keys. My neices got hold of my Omega keys on a day-trip to the beach once. When we came to leave, the car wouldn't unlock. The girls had pressed the button repeatedly, far enough away from the car that it couldn't "hear" it - when we returned to the car, the key was several steps ahead in the programmed sequence and was "out of phase" with the car's receiver. The local Vauxhall dealer re-coded the alarm and keys, and although he wouldn't say exactly how many steps ahead in the numerical code sequence the car would read, I believe that if your keys are more than 5 or 6 steps ahead of the car, the car won't recognise them! You have been warned!

quote:

if you seen top gear jeramy clarkson was using a car fob at its maximum distance it worked but then he went ten feet back it didnt work so he put it to the side of his temple and it worked how the hell did this work he doesnt have a clue but its clear that your eyes amplify the signal in some way

As Sea Spaniel said, don't believe everything you see on TV, it would be impossible for a keyfob infrared or radio signal to pass from the temple to the eyes, be magnified/amplified there & transmitted to a car's receiver to affect the c/l or alarm system.

just wondering about the Vauxhall key thing, how does that work with the spare keyfob then? Does the car's system know which fob is being used and store the information for both fobs?

i have tried the radio key fob to the head and it does work.

DMF

I will now go out and try this myself. (I cannot believe I am going to do this - something for You tube perhaps!)

the over heating thing is not strictly true it only applys to cars with radiators(water cooled) and not to aircooled cars i.e old vw bugs they only break down when you are trying to sell them

The key fob to the head thing works by using the body as a radio aerial and thereby increasing the transmiting distance of the remote.

Same principle as having a weak (music) radio signal and trying to move the aerial to get a better one and finding that when you touch the aerial the signal improves. You increase the size of the aerial when you touch it and the same applies to the car remote (as long as it works by radio signal and not infra-red!) thus increasing it's transmitting distance.

quote:

Originally posted by Sea Spaniel:
DMF

I will now go out and try this myself. (I cannot believe I am going to do this - something for You tube perhaps!)

It works! I wouldn't have believed it. I went to my car and got just out of range. Then touched the key fob to my head and it worked.

Gob smacked or what!

quote:

Originally posted by Sea Spaniel:

quote:

Originally posted by Sea Spaniel:
DMF

I will now go out and try this myself. (I cannot believe I am going to do this - something for You tube perhaps!)

It works! I wouldn't have believed it. I went to my car and got just out of range. Then touched the key fob to my head and it worked.

Gob smacked or what!

Apparently this works with some cars and doesn't work with others. I recently tried it with my dad's 1997 XJ and it didn't work.

As for myth 1, I'm not sure if it would work, but I wouldn't like to be in that situation. Aswell as radiators, I think you also get what are called "sweat tanks", which I don't know much about. Why not just open the bonnet if you are likely to be stationery for a while (but don't remove the radiator cap or touch the actual block).

I have a friend with an old Astra who use this technique a couple of months, So I can confirm it.

in relation to copying car signals, i know of a thieve ring that was caught.
the new renaults have a card you keep in your pocket. when you lift the exterior door handle, the car requests a code from the card. these guys would follow you away from your car, while one person stayed next to it. lift the handle, car unlocks. you dont know its happened. using rf signal boosters it worked up to half a mile away.

you need to press the remote control keys several hunderd times before it loses sequence, and wont work anymore. (either 200 or 500 times, can't remember). you will need a working key to reactivate the other key.)
the codes work on a rolling code sequence, so car says car says x, keyfob says x+1. built into the system is the fact that you'll accidentally press it a few times, but not an infinite number of times. you generally need the master key (usually coloured red) to add other remotes. or a salvage cars cpu and keys

why did you revive a 6 month old myth
but I'll add my 2-bits in too

my dad had a stubborn car that would over heat so he would do th e heater thing and it did work!

i heard that if u tie a guitar string on the end of a cars muffler and rev the engine, it could shatter glass. i have no guitar strings on hand so i have yet to try it.