K bike security

I've had an intermittent ignition problem for a few weeks since it started raining, finally tracked down to the ignition switch itself when it got severe enough (symptoms: tacho needle moving, battery warning light glowing and of course, engine stopping). Pulled off the rubber boot on the back and could feel the red terminal was quite hot. So I checked the schematic and put a clip lead across 2 wires .. hey presto ignition on and off I went to the shops. Used the kill switch to shut it down so I didn't even bother to take a key with me.

Now you can do this in about 20 seconds with absolutely no tools at all though I am not sure if my bike is maybe missing a cover under the ignition switch ?
So short of using the steering lock which is a right pain can anyone think of an ideal solution to improve simple ride away security.

I am thinking of maybe a hidden switch to short one of the important lines on the ignition module to ground to start with, but I'm sure we could come up with something better.

I'm an electronics tech so I'm happy to build something up if anyone has a good idea.

ps .. deliberately did not mention the word h0tw1re (<- thats a cuppla numbers in there) so hopefully this thread won't pop up in google for the bad guys.

Just going to log some info here as I look at the electrics, it may come in handy for someone oneday.

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Just measured the current through ignition switch (red - green only) with motor not running is 1.2A, with the motor running is 3.2A.

Ignition switch only directly (unfused) powers the load shedding relay coil and the kill switch, the other side of the load shed relay coil is connected to ground via the starter motor, so an open circuit starter motor will leave a lot of the bike un-powered. I figure the reason for doing it this way is so the relay drops out when the starter is operated to reduce load on the battery and stop spikes blowing globes etc.

the kill switch then powers the ignition module, coils and the high side of the fuel injection relay coil. this relay is supplied with unfused power and is controlled directly by the ignition control module. power from fuel injection relay runs the injectors and injection control module

so basically (I believe .. untested) you could pull almost every fuse except fuse 6 from the bike and it will still run if the ignition switch is used and the fuel injection relay is present, fuse 6 is required for the fuel pump. conversely .. if the bike doesn't run .. its the ignition switch, fuel injection relay, fuel control module or ignition control module or fuse 6. blown fuse 6 could be faulty fuel pump or really blocked fuel filter.

fused power directly from ignition switch (via fuse 1) then goes to the bulb monitoring unit, brake light switches and the instrument cluster. I imagine that pulling fuse 1 will also light the alternator light if the bike is running. I'll test it later.

power supplied from the load shed relay runs to the headlight completely unfused. So no headlight is either headlight switch or load shed relay, pressing the passing switch uses power directly from the load shed relay so no high beam with the passing light is a failed relay, open circuit starter motor or bad earth.

power from load shed relay then goes to fuse 7. power from fuse 7 .. horn relay, radiator fan and indicators (flasher unit 15).

fuse 2 is parking lights and instrument lights.

fuse 3 clock and indicators (flasher unit 30).

fuse 5 .. special equipment and anti theft module.

fuse 6 .. fuel pump and temperature sensing unit.

fuse 4 .. spare direct from battery.

Being an electrician I can apreciate the ability to "make it work".
But in your situation, why not just replace the switch instead of trying to go around it.

I've had more problems with my side stand switch in the wet than any other electrical component to date.

I have seen/read about much of what Drake has done to his bikes. Alot of it is just a "see if it can be done", challenge.

Stoney,
As Scott says replace the offending switch, if cleaning and a contact check will not repair it, you can also easily break the feed from the battery to the Starter relay and fit a heavy duty keyed switch there which will not only be useful to lengthen the life of the starter relay, by not allowing a heavily discharged battery to seize the contacts of the Starter relay, but act as an anti-theft device too!

What a passing switch/light?

Last time I used the bike I had a fault whereby I only had full-beam, previously before I re-wired the front en headlight the feed to the halogen bulb used to get very hot, I put this down to a bad earth and so fitted an extra earth wire

Now the Spring is on its way, I will have to re-check everything as an MOT is due to re-tax the machine.

Cheers

JBW

Zitat von "Stoney"

So short of using the steering lock which is a right pain can anyone think of an ideal solution to improve simple ride away security.

The water temperature sensor is feeding information to the EFI (pin #10). If the bike is overheated, you won't be able to start the engine until it cool down.
With this information, you can see that it would be easy to short the water temperature sensor in order to disable the fuel injection. Since this is only a signal (negative) going to the EFI computer, it should not draw any power.
I have not seen the BMW alarm system, but it partly plugs on the temperature switching unit. They maybe using this trick to immobilize the bike.

On both of my Ks, I have a toggle switch on the ground coming from the battery. This is very handy particularly if the starter relay get stocked. If you turn off the ignition, the starter will continue to turn. You shut off the ground and it stops.

Sorry guys, I wasn't clear .. I fixed the switch same day, centre contact was grubby.
My post was more along the lines of adding some basic security so someone without a key can't get it going in 20 seconds.

The rain also gave me another problem, intermittent clock when indicators activated but only if the front indicators where connected, this was straight after I had the fairing off and put an aftermarket 10inch thermo fan in the old girl.
I was wondering what I had broken so I was checking out the circuit for the 3rd time in recent weeks and thought I would post the notes above.

Intermittent clock was dirty fuse contacts, they would work ok for the clock or only one lamp but adding the front lamps was enough to cause the fuse contact to bugger up and the clock would die.

Zitat von "k100beemer"

The water temperature sensor is feeding information to the EFI (pin #10). If the bike is overheated, you won't be able to start the engine until it cool down.
With this information, you can see that it would be easy to short the water temperature sensor in order to disable the fuel injection. Since this is only a signal (negative) going to the EFI computer, it should not draw any power.

Yep, perfect .. I came to the conclusion the other day that the obvious ideal area to connect anything to is going to be the existing alarm connector as everything needed is going to be already there. I'm going to have a look on ebay and see about integrating a simple alarm/immobiliser with the existing connector.