Remote Locking On 4.3

[three5]

Hi Folks,

Parked up outside our local school the other evening ( to go to a meeting ). Another guy with a Saab parked beside me. When we came out, neither of us could get the remote unlocking to operate on our cars. I thought it was a coincidence on a very cold night. Anyway, to eliminate a possible cause I changed the Battery in my "keyless" fob. Parked in the same place on Thursday evening and the same thing happened. Have parked there on numerous occassions during the day with no problem. I found out there was a 11kV/415v sub-station in the basement ( 4m away from the car ) but can't see how it would affect the car, particularly just at night. AFAIK, they have to do EMC testing on cars ( and just about everything else ) these days. Anyone got any ideas?

[dave.m]

There have been a few threads on this very topic. Seems to caused by wireless broadband and other sources of interference.

Try the search function to see other threads.

[three5]

There have been a few threads on this very topic. Seems to caused by wireless broadband and other sources of interference.

Try the search function to see other threads.

Cheers Dave,

totally forgot about wireless networks - definitely loosing it! They have a damm great WAP just inside reception. If I have any further problems with it, I'll turn the power off while I start the car :). Many thanks.

[bothwell_buyer]

try not to be tempted to remove the cabling from the sub-station - a guy did that next to our yard and got blown 40' in the air then had severe burns and breakages....and his pals lifted him away to hospital...the police spent a day looking for a well-fried corpse!!

[shcm]

There have been a few threads on this very topic. Seems to caused by wireless broadband and other sources of interference.

Try the search function to see other threads.

Cheers Dave,

totally forgot about wireless networks - definitely loosing it! They have a damm great WAP just inside reception. If I have any further problems with it, I'll turn the power off while I start the car :). Many thanks.

While I should never say never, I tend to disagree. wifi is up at 2.4GHz. The remote locking receiver is down at about 434MHz. I doubt that there is enough radiated power from the wifi to get a significant amount of signal through the bandpass filter that is probably on the front end. Then it would probably have to be big enough to drive the front end mixer into compression. I am assuming the receiver is at least a reasonable design, for its cost.

Then again, I've know harmonics of unsuppressed mains switched mode power supplies play havoc, even as high as 400MHz.

Go on, prove me wrong and switch the access point off!

Chris, there are more likely higher power, in band devices. If you want to PM me the rough co-ordinates, I can do a quick check of some.

[pmb]

Working at tv transmitter sites for many years we used to get problems with Rover cars which had to be dragged off site before they would talk to the key. Have you been there before and are there any masts/aerials in close proximity? Where abouts in Yorks , I'll have a think if anything has changed assuming you've not had problems before ? If it happens again it would be worth taking it up with the school.

[anchorman]

My mate couldn't get into his Avensis for love nor money after fitting one of these wireless alarms in his garage. It was a Toyota dealer that told him to look for such things and unplugging it cured it straight away.

[shcm]

Working at tv transmitter sites for many years we used to get problems with Rover cars which had to be dragged off site before they would talk to the key. Have you been there before and are there any masts/aerials in close proximity? Where abouts in Yorks , I'll have a think if anything has changed assuming you've not had problems before ? If it happens again it would be worth taking it up with the school.

The early Rover systems unfortunately had no front end filtering (some was introduced later), very little internal receiver screening, not great mixer performance and only used the UHF side of things to disable the immobilisation. Later there was an emergency key access code, that bypassed the RF side of things altogether, but they did a bad job of letting people know about it and it was a bit of a fiddle to use. Transponder based system for immobilisation, tend to be less susceptible.

Yes, well, TV transmitters are serious bits of kit! A TV transmitter @ say 1MW erp compared with wifi @ about 100mW Max erp. Only a 70dB difference!!!!!!!

My mate couldn't get into his Avensis for love nor money after fitting one of these wireless alarms in his garage. It was a Toyota dealer that told him to look for such things and unplugging it cured it straight away.

Those things tend to use the same unlicensed bit of the spectrum as the key fobs, so it is not surprising really!

[three5]

Working at tv transmitter sites for many years we used to get problems with Rover cars which had to be dragged off site before they would talk to the key. Have you been there before and are there any masts/aerials in close proximity? Where abouts in Yorks , I'll have a think if anything has changed assuming you've not had problems before ? If it happens again it would be worth taking it up with the school.

The early Rover systems unfortunately had no front end filtering (some was introduced later), very little internal receiver screening, not great mixer performance and only used the UHF side of things to disable the immobilisation. Later there was an emergency key access code, that bypassed the RF side of things altogether, but they did a bad job of letting people know about it and it was a bit of a fiddle to use. Transponder based system for immobilisation, tend to be less susceptible.

Yes, well, TV transmitters are serious bits of kit! A TV transmitter @ say 1MW erp compared with wifi @ about 100mW Max erp. Only a 70dB difference!!!!!!!

My mate couldn't get into his Avensis for love nor money after fitting one of these wireless alarms in his garage. It was a Toyota dealer that told him to look for such things and unplugging it cured it straight away.

Those things tend to use the same unlicensed bit of the spectrum as the key fobs, so it is not surprising really!

So it's not just me then: http://news.bbc.co.uk/1/hi/england/8505314.stm

Someone else with the same problem in Windemere :(

I've not managed to nail the cause yet but thanks for everyones thoughts

[anchorman]

Chris

Do you know a radio HAM? I bet they could find if there are any stray signals. You could hire shcm - he will find it with some gadget.

[shcm]

Looking at that beeb item, well traffic lights do appear to sometimes radiate a load of RF crud in my experience, but I wouldn't expect the field strength to be anywhere near enough to cause those problems.

Somebody with a spectrum analyser would soon sort it out. You can even get a fair bit of info from a simple handheld scanner/receiver. The beeb themselves should have some people capable of doing that, but of cause, it stops a "good"(?) story and journalist probably prefer to just talk ***locks anyway, rather than solve the problem.

[RaverT180]

Hi Folks,

Parked up outside our local school the other evening ( to go to a meeting ). Another guy with a Saab parked beside me. When we came out, neither of us could get the remote unlocking to operate on our cars. I thought it was a coincidence on a very cold night. Anyway, to eliminate a possible cause I changed the battery in my "keyless" fob. Parked in the same place on Thursday evening and the same thing happened. Have parked there on numerous occassions during the day with no problem. I found out there was a 11kV/415v sub-station in the basement ( 4m away from the car ) but can't see how it would affect the car, particularly just at night. AFAIK, they have to do EMC testing on cars ( and just about everything else ) these days. Anyone got any ideas?

Hi Just picked up on this thread had something very similar happen to me last year whilst at holiday home. Car wud not unlock one morning even took the emergency key thingy out of fob and zilch nada nothing. Phoned number 1 son to bring over spare fob and yes, just before he arrived my remote fob worked again. Interestingly the site I was on had just put up wireless internet masts but it aint happened since although dont want to tempt fate! Gawd wot with this prob the dreaded run flat tires and the recent televised problems my future money will go to Mr F not Mr T.

Regards

J