is this the cause of EWS failure?

[snoopy]

There's plenty of reasons for an Xbox 360 to fail.

For the ring antenna problem, I think the ring component was either poorly specified in the first place, or poorly made and poorly tested. I think the latter is more likely - the automotive components business operates on low margins. This is why quality control is so important. Some suppliers and/or batches may be ok and others may not have the specified inductance and/or excessively high resistance.

The effect of an out-of-spec ring antenna would be weaker EM coupling between the sensor circuit and the key transponder chip. This will make the system less reliable and more susceptible to EM interference, hence the EWS failures tend to happen near forecourts, power lines, transmitter masts etc.

Honda have been shipping bikes with HISS for years ...

This is incorrect, the antenna is simply a wire. No EM is going to break it.

 

[Ali-bear]

This is incorrect, the antenna is simply a wire. No EM is going to break it.

This is correct and I never said that. RTFP

 

[Ali-bear]

The antenna is usually enamelled copper wire for transponders and very thin (the thinner and more windings the better it picks up a signal). It's failure is probably down to vibration; the root of most motorcycle problems.

This is incorrect - the ring will be part of a tuned circuit - the ring must have the correct inductance to work properly.

I'd also hedge a bet that's what kills the fuel controller.

This is incorrect - its water ingress that kills the fuel pump controller.

 

[Davy F]

possibly UV altering the plastic of the ring antenna case, preventing proper communication with the key

Very unlikely as alot of EWS failures happen within the bikes first 1000 miles (ask Thunder).

 

[GSmonkey]

You're not meant to use mobile phones at forecourts as you are in a cloud of fuel vapour from the tank displaced during filling. Given ideal conditions this could form a flammable cloud. Your mobile phone has sufficient energy to ignite it - albeit under fault conditions.

 

[shugie]

This is incorrect - the ring will be part of a tuned circuit - the ring must have the correct inductance to work properly.



This is incorrect - its water ingress that kills the fuel pump controller.

I thought the jury was still out on this, with overheating being as much a suspect as water ingress?

Vibration might play a part in failures of both the EWS and FPC. Might!

The EWS is a bit more complex than an antenna I suspect, the ring antenna around the key socket is connected to some electronics in the rest of the housing, and this circuit sends a code to the ECU on the canbus. It would not be practical to send the RF signal along the wiring loom to the ECU. So there are probably several components buried within the EWS unit, any one of which might fail, although if the circuit is "potted" in resin, then vibration would be less likely to cause a failure other than at the connecting points.

There might be several causes of failure.

 

[Owen Snell]

You're not meant to use mobile phones at forecourts as you are in a cloud of fuel vapour from the tank displaced during filling. Given ideal conditions this could form a flammable cloud. Your mobile phone has sufficient energy to ignite it - albeit under fault conditions.

This is correct. In fact, the phone or any other battery operated equipment can produce a spark (however tiny) during normal operation. All of the electic forcourt equipment is designed to hazardous area standards and so is 'explosion proof'. Obviously, there are a lot of other spark hazards on a motor vehicle, which is why you switch off when filling up. The risk with a phone may be tiny, but if everyone used their phones when filling up, at some point there would be a big bang.

 

[(RIP) Kaister]

I've got it !

The cloud of fuel vapour being displaced from the tank causes the Antenna to stop working.

lateral thinking...see ?

 

[John Armstrong]

The risk with a phone may be tiny, but if everyone used their phones when filling up, at some point there would be a big bang.

Surely the greater risk is allowing internal combustion engines to run when other vehicles are refuelling

 

[cookie]

Surely the greater risk is allowing internal combustion engines to run when other vehicles are refuelling

diesels should be ok.

petrol vehicles are not allowed in hythe (and probably others) BP depot.

 

[Owen Snell]

Surely the greater risk is allowing internal combustion engines to run when other vehicles are refuelling

Yes, plus all of the electrics that are not protected on vehicles like starter motors. You normally need a spark arrestor in the exhaust to get into a hazardous area in a refinery, depot etc. Petrols and diesels (hot particulates from diesels).

Someone has done a risk assessment here, and risk assessments are based on reasonable mitigation to give the lowest possible risk. It is perfectly reasonable and easy to stop mobile phone use on the forecourt and the risk is increased by proximity to the hazardous vapour. The mitigation for an engine is to turn it off when fuelling, and there is not really a lot else they can do, so some risk does remain that is too difficult and unreasonable to eliminate.

 

[Deleted Member I]

I suspect the following ..

1. Design flaw from the beginning to cut cost
2. When tender out to manufacturer .. problem could have been prevented by asking for higher quality output .. to mask design flaw
3. As it is a different BMW bod making the purchasing decision, they went for cheapest and "thought" lowering the tolerance levels would be ok .. not knowing what the design bod had done

Why would it have happened. CEO/Director level decision to look for cost savings in producing products. So message to bods were save cost at all cost.


Similar thing has happened to Mercs. They were without doubt the best cars in the world. The testiment to that is the number of old Mercs in developing countries still working! Now .. a Nissan probably has better realiability record.

I suspect the same thing happened in Munich.

 

[cookie]

got mine done, picked it up today.

more questions reveal it's not necessarily UV related, but the plastic is definitely a suspect. seems most faults, and the *campaign* are focussed on 07 and 08 models.

'nother thing to argue about...

my bike also had new engine gearbox seals fitted. these are a new type with lo tech felt facings on them. never seen anything like it. this felt protects the seal from clutch dust, thought to be the cause of premature oil seal demise on these models.

 

[RickG]

these are a new type with lo tech felt facings on them. never seen anything like it. .

Fantastic. Felt eh? My 1956 Panther used felt seals to keep (some) of the oil in. Let's hope it is the cure.

 

[trebor]

I think the EWS antenna is more than just an antenna, as someone else pointed out, there are probably other components in there, it wouldn´t be practical to run the antenna back to the electronics.

I think the problem is down to RF interference since most of the faults seemed to have occured on petrol station forecourts. I suspect that there is a particular frequency sensitive component used in the design of the ones that fail. The relative high power of the RF transmitters used in mobile phone cells is probably high enough to take this circuit out or damage it. The newer units probably have some kind of filter, or other protective device, built in to them.

Bob

 

[cookie]

I think the EWS antenna is more than just an antenna, as someone else pointed out, there are probably other components in there, it wouldn´t be practical to run the antenna back to the electronics.


Bob

there are certainly printed circuits inside the attached box that sits in front of the headstock. i've seen a smashed one.

 

[AndyW]

No idea what's said but this looks interesting.....anyone translate?

 

[John Armstrong]

No idea what's said but this looks interesting.....anyone translate?

Just for you: http://www.ukgser.com/forums/showthread.php?p=1587901&highlight=probst#post1587901

 

[AndyW]

Thanks for that

Apparently the article appeared in BMW Motorcycle Magazine (the english version) - anyone able to do a decent scan of that for me?