Keyfob probs !!

Alan R · Oct 7, 2021

Santa-2512 said:
And to counter your argument... how then does the key fob know the ignition has been turned on, if it is turned off??

One or the other stays in a listening state for activation's... ( eg how does the bike know the alarm function has been activated / de activated etc via the fob)

whilst they are "off" for the purposes of using the bike, each will draw a very low current to keep the relevant listening circuits operational , so they can wake up when

required

Right!

as I said my opinion, not argument, was not troubled by doubt or fact. Here is a fact - I’m not an electronics engineer. I can however apply a modicum of logic to my observations of this type of call and response locking system. I imagine that the key is radio transmitter/receiver that sits there asleep until it receives a wake up signal from the bike. On receipt of such a signal - sent as a handshake request by the bike when the ignition is turned on, it responds with the correct code. This (to humanize it), satisfy the bike and completes the bike start up program sequence allowing the bike to start. The bike will poll the key for response at regular intervals only while switched on, to see if the key is still within range: if it isn’t then the bike will warn the idiot on the seat but will continue to operate. The bike will start the whole handshake procedure again when the bike is switched off. This is why I and many other people buy a spare unchipped key to use on the panniers etc and keep the main key in a pocket. I have seen someone leave the main key in a pannier lock and ride off: if the key were to fall off the pannier unnoticed then :blast

. But you know all this.

It seems to me to be logical that a key battery is discharged in two ways:low energy use, sitting there asleep, listening for a wake up call and higher energy use, transmitting the response code when asked, but only when asked. It doesn’t seem logical to me, that as per your initial assertion, this handshake or polling procedure continues when the bike is switched off. So, the key fob doesn’t “know” that the bike ignition is turned off. It sits there asleep but listening, ever so slowly running it’s battery down. Why some do this more quickly than others? In the words of the man from Delmonte - nobody knows, but it is so.

Alan R

Santa-2512 · Oct 7, 2021

Alan R said:
Right! as I said my opinion, not argument, was not troubled by doubt or fact. Here is a fact - I’m not an electronics engineer. I can however apply a modicum of logic to my observations of this type of call and response locking system. I imagine that the key is radio transmitter/receiver that sits there asleep until it receives a wake up signal from the bike. On receipt of such a signal - sent as a handshake request by the bike when the ignition is turned on, it responds with the correct code. This (to humanize it), satisfy the bike and completes the bike start up program sequence allowing the bike to start. The bike will poll the key for response at regular intervals only while switched on, to see if the key is still within range: if it isn’t then the bike will warn the idiot on the seat but will continue to operate. The bike will start the whole handshake procedure again when the bike is switched off. This is why I and many other people buy a spare unchipped key to use on the panniers etc and keep the main key in a pocket. I have seen someone leave the main key in a pannier lock and ride off: if the key were to fall off the pannier unnoticed then . But you know all this.
It seems to me to be logical that a key battery is discharged in two ways:low energy use, sitting there asleep, listening for a wake up call and higher energy use, transmitting the response code when asked, but only when asked. It doesn’t seem logical to me, that as per your initial assertion, this handshake or polling procedure continues when the bike is switched off. So, the key fob doesn’t “know” that the bike ignition is turned off. It sits there asleep but listening, ever so slowly running it’s battery down. Why some do this more quickly than others? In the words of the man from Delmonte - nobody knows, but it is so.
Alan R

lol it wasn't argument in the sense of an angry argument, but arguments in a theory etc

Always open for a discussion, its the way problems get solved

could it be the opposite prhaps ... that by removing the fob from the active zone, the fob is constantly polling to refind the bike? hence the

power drain& once found it sits in a low power mode mode state waiting for either the bike to wake it up or vice versa

could well be, we have a chicken & egg scenario?

Alan R · Oct 7, 2021

Santa-2512 said:
lol it wasn't argument in the sense of an angry argument, but arguments in a theory etc

Always open for a discussion, its the way problems get solved

could it be the opposite prhaps ... that by removing the fob from the active zone, the fob is constantly polling to refind the bike? hence the

power drain& once found it sits in a low power mode mode state waiting for either the bike to wake it up or vice versa

could well bre, we have a chicken & egg scenario?

I can’t see a system advantage in that situation. Constantly polling must use more energy than just listening. Think about tracer chips in pet dogs, no power supply but the ability to be activated and read by a scanner. Those devices must have the ability to respond to a seeking signal. If one thinks about the car theft scenario where one scroat lifts a car door handle while the other one holds a signal grabber/repeater near the house front door to reach the key fob on the table inside near the door, the initiating action is at the car door. Only then does the fob answer. Your scenario has the fob constantly shouting “where are you?” Whereas in reality it’s the bike that does that call and the fob that responds “here I am.” I think we’re both just guessing but I instinctively feel that the bike is the starting point in the wake up conversation.
The clincher for me is that the little plastic key doesn’t have a power supply but can respond to the bike wake up call when placed immediately next to the signal send/receiver.
Alan R

Neil W · Oct 7, 2021

Oddly enough my last 5 BMW motorcycles have never had this problem, because they had a key , just like the one you still need on your keyless bikes to unlock and lock your luggage, sat nav mounts and seat.

Keyless is a ridiculous solution for a problem that never actually existed

Alan R · Oct 7, 2021

Neil W said:
Oddly enough my last 5 BMW motorcycles have never had this problem, because they had a key , just like the one you still need on your keyless bikes to unlock and lock your luggage, sat nav mounts and seat.

Keyless is a ridiculous solution for a problem that never actually existed

Fantastic contribution!

I never once had a problem with the starter motor on any of my bikes in the 1970’s, oh wait, none of them had one. I lament to this day the insensitive removal by most manufacturers of the cool looking kick start.
Alan R

bosnjo · Oct 8, 2021

I have 2021 GS with standard key. Ordered the bike that way back in January and I wouldn't buy it if keyless was the only option.

newbuild100 · Oct 8, 2021

Neil W said:
Oddly enough my last 5 BMW motorcycles have never had this problem, because they had a key , just like the one you still need on your keyless bikes to unlock and lock your luggage, sat nav mounts and seat.

Keyless is a ridiculous solution for a problem that never actually existed

I have to agree. It leads to another question …. How far have you ridden away from home, only to realise your key is on the kitchen top/garden seat/garage etc etc ???

shifty · Oct 8, 2021

newbuild100 said:
I have to agree. It leads to another question …. How far have you ridden away from home, only to realise your key is on the kitchen top/garden seat/garage etc etc ???

i did this the other day, started bike , went into kitchen to get helmet and must have put key on the worktop, walked back out to bike and the dash told me the key was not in range and would not be able to be restarted if switched off,,,,, so i wouldnt have got further than the end of the drive without realizing ,,, :beerjug:

richtel · Oct 8, 2021

Crikey. Look, the fob is a powered transponder. It contains a low-power receiver which is constantly listening for a probe from the bike's EMU transmitter. When not running, the bike will only transmit a probe if it needs proof that the owner is trying to do something. If the fob recognises a valid probe it'll transmit a corresponding acknowledgement code. If that code is recognised by the bike as correct, the bike will do whatever the owner is trying to do- switch on the ignition, open the fuel cap, whatever. The biggest draw on the fob battery will be when it's responding to a probe, or one of the buttons is being pressed.

If the battery is dead, the fob becomes a passive unpowered transponder- it'll still receive a code but as it's unpowered the transponder is powered only by the RF coming from the bike's transmitter. The fob's tranmitted response is so low power that you need to hold the fob right up to the bike's receiver under the tail. That's the same with the plastic emergency key.

Fenlander Strasse · Oct 17, 2021

My fob lasted 18 months on it's original Panasonic battery. The Duracell replacement lasted about 30 minutes, so I installed another Panasonic and it's fine now.

malcopopolo · Oct 24, 2021

Neil W said:
Keyless is a ridiculous solution for a problem that never actually existed

Disagree - keyless prevents some scrote taking your key while parked at traffic lights. keyless stops you leaving keys in ignition when popping into the biker cafe

Keyless means that you are less likely to lose the key as it is always in your pocket/jacket.

malcopopolo · Oct 24, 2021

Fenlander Strasse said:
My fob lasted 18 months on it's original Panasonic battery. The Duracell replacement lasted about 30 minutes, so I installed another Panasonic and it's fine now.

Interesting- my car and bike are keyless. Purchase my batteries from a well known supermarket. duracells purchased on line never worked properly. Duracells from a genuine known source ie not on line and work fine. I think like memory cards there are a hell of a lot of fakes. Duracella re more likely to supply direct to large supermarkets or large camera chains.

Who knows?

Keyfob probs !!

Alan R

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