K11 Owners Group

[robbocop33]

Bouht a 1992 k1100lt a few weeks ago.Temp gauge works fine,bike doesn't overheat,temp gauge sits right in the middle.Bike runs well enough albeit with slight hunting at idle, and the fact the cooling fan just comes on,but won't switch off??
It will switch on during normal driving,maybe after 10 miles or so but varies.Don't have to be stuck in traffic it can just switch on at say 50mph and just stays on??From little bits i've read it must either be the relay or the temp sensor.Does the temp sensor at the top of the engine have a little multi plug type connector on it?(just for recognition purposes)
Thanks in advance for any help!

[Inge K.]

Welcome! The problem could also be the Motronic unit which sends a signal
to the relay based on the feedback from the sensor.

Easiest way to measure the temp sensor is at the Motronic connector,
contact #21 & 32......lower row, count from the rear (also the empty slots)
starting with #19.

At 20C you should read around 2500 ohms, at operating temp you should
read around 270 ohms.

[robbocop33]

Ive plumped to replace the motronic unit,found one cheap enough!Any concerns i should have while carrying out the swapping of units,battery off first i take it?

[Inge K.]

It shouldn't be any problem to just remove the connector from the old unit
and plug it into the "new" unit.

[robbocop33]

Ok,thanks!

[Inge K.]

FYI, it's a different unit from 07/93 (-94 year model), and with or w/o a cat.

[robbocop33]

[robbocop33]

Can someone confirm for me that the motronic unit i need is the metallic unit that sits horizontally,lying flat facing you on the left under the seat?

[Inge K.]

[robbocop33]

Just as a matter of interest,if the water temperature sensor was faulty and falsely showed an overheating situation would the ecu trigger the cooling fan relay?

[Inge K.]

Yes of course it would, but I would also expect some running problems during start and heat up, when the sensor is faulty.
But not necesserily, it would depend if the sensor is wrong over the whole range (most common) or just part of it.
Your fan should start at around 140 ohms.

[robbocop33]

Only running problem is slight hunting at idle.Starts first time,runs well enough.It does have nother habit of cutting out at fairly low speeds when im coming down the gears to draw to a halt.

[robbocop33]

What would happen if i unplugged the small two pinned connector going down to the cooling fan?Would the motronic go haywire or would the fan just not come on?

[Inge K.]