Hello.
that's it, i'm in trouble here.
for the second time now i've been towed to my garage.
On the road, after one hour trip, the bike stop working. exactly like if you switch the kill switch at off.... once on the side of the road, the bike will not restart.(even no crank...) call the towing... go to my garage. The day after, on the morning, all is ok, it start and every thing is normal.
One week later, the sun is back, take the bike.... and voila, the same shit happen. It stop completely. If you try to start, only the pump is primed when i hit the start button, but the starter will not engage. The starter relay is receiving power when i push the start button (on the black-yellow wire) but the brown-red wire also is receiving power so the relay do not engage.... for shure i can jump the relay, and the starter will turn but no spark, no start. So, the igintion control module is not supling ground to my starter relay.... why.
I did read bertrand vogel(crazy frog) troubleshooting pages... and i'm stuck at the temp sensors..... it is writed that if the bike is in over heat situation, the bike wont start...ok so i did check ohm value of temp sensor at the fuel module, and it's in the spec.... now i'm searching for the temp sensing switch switch ,where is it? do you have an other idea....
Thanks
Serge

Serge, I ll suggest you to check and clean every contact on the bike. Once I had similar symptoms and found that the wires from right handlebar (start, kill, etc) were coroded at the socket under the tank. After cleaning and tightening it never happen again. Could be something stupid.

Did you check hall sensors?

Regards

Salut Nino
I.ll check that. i will remove the handle bar switch...
about the hall sensor, can they cause the bike not to start?
Serge
also i did open the ignition control unit,and i've got some RUST coming out of there....

dewalque wrote:Salut Nino
I.ll check that. i will remove the handle bar switch...
about the hall sensor, can they cause the bike not to start?
Serge

If hall isnt OK, when engine get hot it could cut. The test is to heat hall sensor cover with heat gun. If cut then is probably hall sensor. Its expensive, but you can put used item

the temp sensor is bolted into the water riser stub ....behind the radiator .

you can access it by the right hand side ...take the air intake tube off to allow a little more access (of corse the right side lower fairings as well )

there is one of those funny wrap around circlips that hold on the connector (square shape thingy ..i use a jewlers screwdriver to lift out the clip itself )

it could be common that the electrical connections in there become corroded ...so take out the sensor (19mm) plug the hole .(not much fluid gets out if your quick )

clean up the little prongs of the sensor contacts , clean up the thread of the sensor ...and make sure you clean the socket parts of the plug connector . use a new copper washer for the seal, not the aluminium one.

all this usually resolves running "over rich" problems as the sensor is a high value as it is cold and goes low as it heats up this process makes sure that the fuel management computer adjusts correctly ( pin 10 on the fi computer to test ...)



but it sounds like you are experiencing a low value not a high one ..... like an engine overheat issue .

are you sure that the cooling fluid is circulationg correctly ?.... is the thermostat working correctly ? it could be faulty and the temp sensor is seeing an over heat issue .....if it stops again i would be pulling the fi connector off and testing the value to confirm this .

just a note ...we have seen faulty ignition switches in the past and it would be worth testing that properly ,,,im thinking that if it was high resistance ...it might work for a while then as vibration affects it some components of the electrics stop ? just a thought

have a look at the altenator charge as well ....is the battery discharging ?...and after leaving it over night it recovers a bit enough for a start ?



nino has a good point too ....check and clean all the connection under tank

i know the alternator is not fully functional. it chage ok but not at idle.
On the wiring diagram, i can see the temp sensing switch,. but in the bike, i do not see somethink like that. Perhaps in the instrument cluster?
about the value of the temp sensor, it was easy to take the value at the fuel computer, pin 10 at room temp. 2.9khom. like supposed...
So rust on my module of ignition... not easy to open completely, i've got to remove soldering point to acces the other side of the printed circuit....
i'll update
Thanks in advance to take time
Serge

Just a quick answer as I have to scratch my head on this one. I don't believe that the problem is with one of the computer, the Hall sensors or the water temp sensor.
They are not controlling the starter.
If the bike overheat, the starter will turn but the fuel injection will be inoperative.
Just as a quick test: WITHOUT the ignition turned ON, could you try to put a +12v on the starter (In Quebec you should have a set of booster cables which is the type of wire gauge you will need).
This is just to test if the ground is traveling through your starter.
Please let us know if the starter is turning this way.
My first tough is maybe a bad starter or bad ground.
I also agree with the probability of a bad kill switch or bad wire feeding it (most probable cause).

CF

Hello Bertrand
i did try it right now. the bike did crank.
now, also i did put back that ignition box, and it cranked one time.... then basta. (the fuel tank is removed so the motor did not start for shure)
i'll remove and open the ignition switch and the kill switch. but also i'm going to buy an other ignition module..... do some one have some think to sell like this one....

http://www.ebay.ca/itm/1986-BMW-K100-IGNITION-MODULE-BOSCH-/220949454906?pt=Motorcycles_Parts_Accessories&hash=item33719d203a

Thanks
Sewrge

just try to do something when the bike doesn't start.
Switch the horn relay with the load shed relay (I believe they are the same).



The fact that you get power on the 2 sides of the starter relay's coil may simply indicate a faulty load shed relay .

ok
that was done when stuck on the road.... with no luck. i even try it right now with no luck.
when i speak about ignition module, it's b'cause i've got rust coming out of there!.... and also that this box is controling the starter relay by feeding the starter relay with ground.
So if when i unplug the small plug of the starter relay (2 wires, one black yellow, starter switch, and the other one brown red controled ground from the ignition box) and i put a real ground and i put a jumper wire bettwen the black yellow and the terminal at the starter relay, the starter will run when i push the button, but no spark!, and the engine do not run!
i'm going to buy that box today.... i'll have it any way! what do you think of that.... perhaps i should try to open it completely...
....
Serge

This problem seems very like the problem I am having. I have narrowed it down to the fact that it is NOT the battery, starter, starter relay and a few more items but seems very very similar. Mine starts once then runs for a few minutes, cuts out and then will not restart, fuel pump runs but engine does not turn over. If left sitting for a while then it does start and of course cuts out again.

exact.
i did buy the module of ignition...
i've got too much job tooday that i will not be able to work on that today. ( i own a garage specialized in bmw car, and they are easier to repair i think....)
I'll update for shure
Thanks

dewalque wrote:
when i speak about ignition module, it's b'cause i've got rust coming out of there!....
Serge

You got it Serge!

I just remember.....
It was a recall to replace the ignition modules on the first K100rt because they were not waterproof.
The recall was only good for 10 years (ending in 1985 )

You may want to open the module and clean the corrosion on the board. This may solve the problem.

CF

Crazy frog, i did try to open it!, but i've got to remove soldering point to be able to open completely the box.... i'll try it when i have time.
The new parts is ordered.
Merci
Serge

Hello
So i did solved that problem.
It was the control module of the ignition. all is nice (for now), the bike did start and i did run a 100km whitout any problem....
Thanks CF for all the research you've done before, it helped me in my diagnostic a lot.
Merci encore
Serge