Odd one....
- Thread starter King Rat
- Start date
Back home... the trip on the trailer wasn't in vain. Got to the workshop and tried to start it, well turned on to listen for pump. It was at this stage I noticed there was no fuel gauge, but the clock was running fine, and keeping time. So I wriggled the key a bit and the LCD for the fuel gauge flashed and then kicked in with backlight and everything. The fuel pump started running at exatly the same time.... so I pressed the tit and she fired up straight away, 20 seconds later the red charge light went out. 
Turned off and on a few times - it is a dicky connection in the ignition key jigsaw puzzle. Squirted a load of electrical cleaner into the keyhole (it made me feel good) and fiddled the key in and out and on and off a few times to try and get the cleaning fluid around the place. It has worked, sometimes with a bit of a wriggle of the key needed, since. So at some stage, when I can find out what is involved, the key switch is going to have to be sorted out. Or a new ignition switch bought and fitted to my key slot.
On the positive side, the battery has had a really good boost charge all day yesterday and seems fine. The bike ran as sweet as a nut too. Quiet, no rattles and smooth as silk.
Turned off and on a few times - it is a dicky connection in the ignition key jigsaw puzzle. Squirted a load of electrical cleaner into the keyhole (it made me feel good) and fiddled the key in and out and on and off a few times to try and get the cleaning fluid around the place. It has worked, sometimes with a bit of a wriggle of the key needed, since. So at some stage, when I can find out what is involved, the key switch is going to have to be sorted out. Or a new ignition switch bought and fitted to my key slot.
On the positive side, the battery has had a really good boost charge all day yesterday and seems fine. The bike ran as sweet as a nut too. Quiet, no rattles and smooth as silk.
Good one Simon 
Further to the above .... just make sure you do isolate the problem and get it fixed. You don't want the engine cutting out halfway round a bend or on an overtake 
It's not the classic broken wire in the short section of wiring to the bottom of the ignition switch is it ?
Spraying anything in the keyhole will only lubricate the tumblers, not the contacts.
The contacts are in the bottom "button" part at the bottom of the tumbler assembly.
Spraying anything in the keyhole will only lubricate the tumblers, not the contacts.
The contacts are in the bottom "button" part at the bottom of the tumbler assembly.
Further to the above .... just make sure you do isolate the problem and get it fixed. You don't want the engine cutting out halfway round a bend or on an overtake
OVERTAKE? What's one of them then?
Cheers tarka - I will have to give the bike a good run to burn the fuel off before I can take the tank off. It is absolutely brim full. Then, I shall have the chance to take the tank off again and get it sorted properly - the left hand fog lamp isn't working either, there is a 0.5v drain on that circuit somewhere too. Andy with his fancy electrical instruments found that. I suspect that some wiring will need to be done. Hopefully we can remove the dreadful Datatool alarm at the same time. I hate it.
IF the Hall Sensor packs in the fuel pump will not work otherwise it would fill the cylinders with petrol, with possible theatrical results
Absolute 100% utter bollox x10.
Well at least it turned out to be a workably cheap fix
Absolute 100% utter bollox x10.
Back to you Sir
From a top time served BMW Technician, still there doing it at one of the biggest dealers in the country, done all the courses, even sent to Spandau to 'rub shoulders'
"The motronic unit briefly earths the fuel pump relay on initial ignition on to prime the system. From there on it relies on a crank sensor signal eg hall sensor. Doesn’t cut power. It doesn’t provide the ecu with a signal to switch the pump on. It’s the Ecu that provides an earth for the fuel pump relay"
No Hall Sensor = no fuel pump
I think you're taking the MickyBack to you Sir
From a top time served BMW Technician, still there doing it at one of the biggest dealers in the country, done all the courses, even sent to Spandau to 'rub shoulders'
"The motronic unit briefly earths the fuel pump relay on initial ignition on to prime the system. From there on it relies on a crank sensor signal eg hall sensor. Doesn’t cut power. It doesn’t provide the ecu with a signal to switch the pump on. It’s the Ecu that provides an earth for the fuel pump relay"
No Hall Sensor = no fuel pump
Sent from my SM-N910F using Tapatalk
I think you're taking the Micky
I don't think so kid
.... and we all know Tim's expertise on all things mechanical on King Rats 650 gearbox sprocket thread ... "They all do that"
Otherwise gone quiet on here
I have a new ignition switch ordered, should be there in the morning.... I hope it is a simple swap.
Back to you Sir
From a top time served BMW Technician, still there doing it at one of the biggest dealers in the country, done all the courses, even sent to Spandau to 'rub shoulders'
"The motronic unit briefly earths the fuel pump relay on initial ignition on to prime the system. From there on it relies on a crank sensor signal eg hall sensor. Doesn’t cut power. It doesn’t provide the ecu with a signal to switch the pump on. It’s the Ecu that provides an earth for the fuel pump relay"
No Hall Sensor = no fuel pump
I'll say again.. Absolute rubbish.
In over 30 years of working on BMW's I've had a few bikes that will start and idle all day long but touch the throttle and they die..
Hall sensor were fecked but the bikes started and run.
I've had other hall sensors that have failed completely but the fuel pump has run..
As I've always suggested over the years... If turning the rear wheel with the ignition on can you hear the fuelpump prime ?, if not it's 95% that the hall sensor has failed, BUT if you can hear the fuel pump prime that doesn't mean it's NOT the hall sensor that's failed
. Plenty of examples of me offering this advice over the years, below (there are more).
POST 6 , POST 7, Post 5 - note the 95% advice
Also you haven't explained how the cylinders fill up with petrol if the fuel pump runs continuously without the engine running ?
Take out an injector and supply the fuel pump with a live feed.. No fuel will come out as the injector is closed.
Otherwise gone quiet on here
It'll now stay quite from me, as i have a business to run repairing custoners BMW's..
I'll say again.. Absolute rubbish.
It'll now stay quite from me, as i have a business to run repairing custoners BMW's..
Good one Stepper ... me too
meanwhile I'll get in touch with BMW and tell them they're doing it all wrong
I don't think so kid
.... and we all know Tim's expertise on all things mechanical on King Rats 650 gearbox sprocket thread ... "They all do that"
Otherwise gone quiet on here
You missed the sarcasm.
Some of us have spent a life as mechanical engineers while you spent yours nicking speeding bikers
You missed the sarcasm.
Some of us have spent a life as mechanical engineers while you spent yours nicking speeding bikers
Ha ha .... could be true
But I do hold my City and Guilds parts 1 and 2 in Motor Vehicle Mechanics and Technicians, albeit written on parchment
Eight of my years were spent on Accident Investigation and Stolen Vehicle Investigation duties
I have 50 meter swim certificate if that helps
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