The following article caught my eye, but there are some very inherent mistakes made in this reporting. My comments are at the end.

Mobiles can make brakes fail, warns AA

PEOPLE who use their mobiles while driving risk crashing as they can interfere with the car's engines and brakes, experts have warned.

The AA urged drivers to make sure they were stationary when making mobile calls because the signals emitted by phones can disable the electronic control units fitted in most modern cars. Up to 16million cars built during the past ten years could be affected by mobile radio waves, according to the association. Older cars do not contain the sophisticated electronic equipment and should be safe.

AA spokesman Chris Patience said motorists who had invested in hands-free mobiles so they could drive safely and legally while talking on the phone should be aware of the risks. 'It is the same as aircraft operators asking people to switch off their mobiles while on a plane,' he said.

'The mobile phone is transmitting all of the time. There is the possibility of interference with electronics in the car. You might get a misfire or your braking systems might not operate.'

Mr Patience said drivers could mount an outside aerial on the roof of their car to keep radio waves away from its electronic control unit. However, he said for 'absolute safety' mobiles should not be used inside modern cars.

Car manufacturer BMW admitted mobiles could set off air bags in its vehicles, while the manual for Vauxhall's new Corsa warns owners not to use phones while driving. Honda plans to follow suit and inform new owners about the possible dangers of mobiles. A spokesman said: 'Honda recognises this as a problem and we are doing all we can to stop it from happening.'

"METRO", London Edition - 10 January 2000

One of the fundamental mistakes made in this article is the fact a cellphone is nearly always transmitting in a moving car as it logs on to the next cell while leaving another (i.e. not just while talking). This is a plain fact of cellphones. Furthermore, the cellphone is usually not in a controlled place when this happens e.g. thrown into the glove compartment etc. thus closer to the electronics!

Now, anyone who has used a cellphone near a telephone will realize that these can affect electronics, that is if they are not shielded properly. It must, however, not be forgotten that all electronics sold in Europe have to pass the EMC specifications, one of the criteria being that they are to survive with unduly high levels of RF thrown in their direction. Are the car manufacturers actually admitting they lied about the EMC conformities?

It must not be forgotten that this article was written shortly after the Christmas season, just as a lot of little darlings got cellphones as presents and the networks suffered under the strain of all the new 'toys'. It would appear the "cellphones cause cancer" trick is not working anymore! Maybe this is a new trick to get people to stop driving when using the cellphone. Remember, this is now the law!

However, talking about vehicles and RF; Many have reported that in almost every installation of radio transmitting equipment they've performed in their own vehicles, they've experienced minor EMC problems. One example was electronically operated indicator flasher systems being RF susceptible, resulting in 50-100% increase in flash rate when transmitting. To be somewhat fair, RF power levels are higher and in different bands from cellphones (144MHz and 430MHz being the two most common mobile amateur radio bands).

Based on these reports, it could prove prudent to be far more concerned about these installations than cellphones. Yet some permanent cellphone installations have very high effective radiated powers, as well as operating at a wavelength much smaller than 430MHz.

It could be libelous to emphatically state that manufacturers lie about their EMC testing, especially as they cannot test for non-standard installations. While a flasher unit may not be safety critical, it costs a few pennies to rectify the problem, making one wonder just how serious such susceptibilities are taken.

I am reminded of one story where a ham had just installed an HF rig into his vehicle, was on the freeway doing 75mph, and was talking quite happily. It was at that time of day when band changing was a good idea and he popped in the new frequency and hit the "tune" button. The result was he blew the stuffing out of the engine management system.

He had no recourse either. The manufacturer had obviously done some testing and found their design lacking in EMC compliance. The way they got past this was a small paragraph in the back of the car's user manual that said "no transmitters of greater than 10W shall be installed in this vehicle". C'mon, when have you ever known anyone to read the whole handbook!

Since this article was penned, I have received the most amazing emails and want to highlight one of the most blood-chilling ones to date.

“In January 2003, the steering air bag in a new 2003 VW Passat W8 went off for no apparent reason. The car was parked and the ignition off. The air bag deployed when starting a call on a mobile (cell) phone, which was nearly touching the cover over the air bag module.

“VW in the States has not responded to any requests for information about why this happened. The phone service provider, T-Mobile, has referred me to VW and Motorola, the manufacturer of my V66 phone. Neither have responded to requests for information.

“The information being collected is for a planned media campaign to make people aware of the risk of using a mobile phone inside a car if, indeed, it can be documented that a call can set off an air bag.

What is most fortunate here is the airbag did not pop open in the driver’s face while doing 75mph (120km/h) along a busy freeway! I personally shuddered at the prospect of the adrenaline rush followed by the sudden inability to see where one was going!

What makes me also go cold is knowing that I have driven a BMW that has the cellphone’s car kit antenna situated right above the passenger’s airbag. I would not have been impressed if this had exploded in my wife’s face while having a chat to a client or colleague. Even having the passenger’s airbag appearing for no explained reason can distract a driver sufficiently to cause a major traffic accident.

Please don't get me wrong; I am not against cellphones at all! Also, I am not wanting to have a law saying I am not able to use it while driving. In actual fact, you may be surprised to hear that various police forces don't want this law either as this could impact their work (they often need to use a cellphone, and it doesn't go down very well with the general public when they see an officer of the law break the law!).

Maybe the answer is a "module" one can add to a driving test showing a competence to control a vehicle while engaged in a call on a cellphone. Ah, but herein lies a small rub as one has to then also chose a vehicle who's airbags are not going to violently object to the call being made in the first place!

So the plot is growing even thicker. It would be nice if the real reason to get people to stop using cellphones while driving could be revealed, but I am not expecting motor vehicle manufacturers to rush out and start up media campaigns saying their cars have inherent flaws. They have far too much to lose. But, by not stating that this cannot happen means one is perfectly safe to assume it can… (and the lawyers remain employed!).

Maybe it is time to start collecting information, and I welcome any comments on this issue.

Marc Dekenah

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