Following advice from pictures in this thread the relays are identified. One is labeled 'LSR' on that picture, can someone please tell me what that stands for?

I have a 1989 K100RS (with ABS removed) that blew off the bottom hose whilst looking for oil leak after rebuilding the water pump. The bike was idling for some 10-15 minutes when the bottom hose blew off the water pump. I now think almost for sure that this was my fault for not refilling the cooling system with the correct amount (2.8L) of coolant. I think now trying to remember what was in the container of coolant I drained off and then put back, it may have only been about 50% of what should have gone in (2.8L). For sure a very senior moment, and very costly it was too!

So I can work my way through this bike I am identifying all the relays. From the info in the previous thread, it says that the ABS relay is number three in the picture below, but can anyone identify what relay number 9 is in the big white socket at the bottom please? This is the picure of whats in my bike.





What I did last night on the advice of others in the intro thread

I removed the thermostat last night and heated it up on the stove in a pan of water with a digital thermometer in the pan.
Opening was around 86 deg and it was fully open around 95 deg so I think that its OK, it certainly cycled open/close when I cooled and reheated the water.

I measured the seal in the radiator cap, 25mm ID 36 mm OD so I think that is OK too. However, there was some crud in the cap and I dont know if this had anything to do with the valve in cap not opening. Here is a pic of the cap inside. I dont know if this would affect the safety valve in the cap opening or not. Anyone?




After cleaning that crud out, there was a nice clean white ring. The picture below also has the big sealing rubber ring removed for cleaning, I just didn't put it back yet.





The fan itself is OK as I put 12V on it on the connector at the fan. It runs fast and quiet.

So now I need to check the fan relay circuit.

I need to find out which number relay in the first pic of mine is the fan
I need to check the resistance cold and hot of the temperature sender.

If any of you whizes know what these relay numbers are and the sensor resistance - I'd appreciate it please? I will get there in the end but I'm trying to get this K100 up and running before winter sets in, and I have a long way to go yet.

I have not yet on all the accasions when the bike has been idling in the garage seen the cooling fan cut in. Lots of posts here relating to the fan cutting in but mine never has yet.

Cheers for any help


Dave

LSR= Load Shedding Relay, cuts uneceserry loads when pushing the starter button....
to get max power to the starter.

Relay 4 & 9, which is missing in your picture is ABS relays
(4 warning system, 9 power supply).

Fan relay is number 5 in your picture, info on sensor resistance you find in the troubleshooting guide at the portal.

Inge k

Cheers, thanks for that, and thanks for the very swift reply

Dave

+ 1 inge

there are a few threads about that fan operation throughout the forum dave

just use the search feature

some have found the temp relay to be at fault ...some the connectors ...and some the temperature sensor (mounted on the water stub behind the radiator ) there are 2 connections in there and the body is the earth return part ...so that makes 3 connections really ...i have found mine to be corroded and a good clean up solved my issues

hope this helps

Charlie99

Cheers M8. When you refer to 'temperature relay at fault', is there a further relay connected to the temperature sensor as well as the fan relay, or are you refering to the fan relay?

Cheers

yes ...the fan relay ....has a bit more electronics than a relay ...but basically yes

I took off the radiator (again) today to gain access to the temperature sender. I downloaded the troubleshooting guide to look at the graph of the sender. I heated it to 100 deg as in the suggestion and took the readings as it cooled. Of course my multimeter and temp guage are not calibrated to NAMAS but I dont think they are way out. Below is what I got

TEMP Resistance

100.....390Ω
90.......480Ω
80.......655Ω
70.......870Ω
60.......1.171KΩ
50.......1.618KΩ
40.......2.275KΩ
30.......3.230KΩ
25.......3.910KΩ
20.......4.590KΩ

The slope of the graph does not exactly coincide with that in the troubleshooting guide in the portal.

I'm not sure if this is correct or not, but if this is considered servicable then I guess its in the big temperature relay box. Anyone like to comment on wether or not its acceptable please?

Also the sensor was quite corroded when I unscrewed it and it had a disintegrating chewed up aluminium washer, but the contacts were very clean. Below is picture of what I remocved.

Charlie99 said...

.
there are 2 connections in there and the body is the earth return part
...so that makes 3 connections really ...i have found mine to be
corroded and a good clean up solved my issues

You may be right Charlie99?




Any comments bar insults most welcome

Cheers
Dave

The sensor ground connection is trough the threads and gasket mounting surface, by judging the picture it seems like your sensor didn`t have that good ground connection
(if any at all).

From your resistance measurements it seems like you have measured both elements in series, you must measure between each element and the sensor housing (ground).

If you ground pine #E (violet/green wire) on the temperature relay, the fan should start.
This is one way to test if the relay is still working.
Grounding pin E is the equivalent of having an engine very very hot.
Is the water circulating in the radiator?
Have you tested (removed and cleaned) the thermostat?

CF

Crazy Frog wrote:If you ground pine #E (violet/green wire) on the temperature relay, the fan should start.

Or the sensor connector (other end of the wire), while the sensor allready is removed.

Inge K. wrote:

Crazy Frog wrote:If you ground pine #E (violet/green wire) on the temperature relay, the fan should start.

Or the sensor connector (other end of the wire), while the sensor allready is removed.

This is a bit more tricky as this is a dual plug and you want to becertain that you don't ground the side for the EFI.

I don`t think it would hurt the ECU if you ground that connector.
But the safe and easy way would be to disconnect the multiconnector at the ECU.

dave i agree with inge, the results look like you have measured both terminals rather than body to each terminal separatly .

but yes looks like you have found a primary issue ...ie the corrosion between the thread of the sensor
and the water stub
keep in mind that the stub is aluminium and held in place by 2 steel screws ...it might pay ...whilst you are working in that area to make sure that you at least measure between the water stub and the main engine housing to see that you have a good continuity between both parts ...ie "0" ohms .
that aluminium washer is a pain.... brass makes more sence to me ...i ended up getting a copper washer and tinning it (soldered it ) the reasoning being that the tinning process would be a better medium between the brass and aluminium interface ...besidees it gave me a good soldering point to run a cable to earth propper as extra insurance .

dont forget to clean those connection points in the terminal housing good an proper ..a lot of us use "deoxit" for such things ...likewise the spring loaded connector in the plug top fitting (bit like an injector cap)

good luck ....seems you are on your way to the fix

and you might just get better fuel economy as an added benefit

Inge K.

From your resistance measurements it seems like you have measured
both elements in series, you must measure between each element and the
sensor housing (ground).

Arghhhh. F.F.F Ok do it again tomorrow

Crazy Frog

Is the water circulating in the radiator?
Have you tested (removed and cleaned) the thermostat?

I put a hose through it today under low pressure, all is well. I tested the thermostat with a digiatl temp guage, yes that appears OK, and I know the fan runs OK as well on its own with 12v applied


Charlie99

i ended up getting a copper washer and tinning itand you might just get better fuel economy as an added benefit

I can solder a wire direct to a copper washer for the earth no problem, I might just do that. Good thinking

Well wouldn't know about better fuel economy as I've never riden this bike or had it on the road. It arrived in the back of a van. It was an insurance write off. A catagory C.

I'll do a bit more and re test tomorrow.

Thanks for all your comments. If theres any major change in the readings I'll come back with cap in hand.

Cheers all

Dave

Dirk Digler wrote:, and I know the fan runs OK as well on its own with 12v applied

By testing as earlier suggested, you`re not only testing the fan....
but also if the relay does function.

By testing as earlier suggested, you`re not only testing the fan....
but also if the relay does function.

Yes, understood. I was refering to the actual fan itself as a known working item

I did some more measurments today. Unfortunatly I do not know of the two sensors in the casing if the readings are supposed to be the same as each other when referenced to the casing as a common. If that be the case then they are not. I used two digital multimeters at the same time, the differance between the two on ohms was about 10 ohms differential so I doubt that will cause an issue.

Below is a sketch of looking into the pin end of the connections on the sensor itself (best I could draw sorry), with the bump on the top I call the pins L & R




These are the readings I got today, I took the readings every 5 degrees and the resistance is in KΩ.
Ist column is temp, then left pin, then right pin.

20	2.581	2.442
25	2.301	2.150
30	2.090	1.938
35	1.850	1.702
40	1.625	1.476
45	1.434	1.292
50	1.260	1.130
55	1.115	0.990
60	0.977	0.862
65	0.850	0.745
70	0.741	0.641
75	0.650	0.560
80	0.580	0.490
85	0.492	0.423
90	0.431	0.369
95	0.377	0.320
100	0.305	0.254

Do these readings look OK?
Would you say this temerature sensor is funcional?

Thanks

Dave

These readings looks a bit better than yesterday, your sensor is OK.
EDIT: OK at the low temp end, but to high at the hot temp end.

Many thanks again for you swift reply

I can now make good that earth connection tip and look towards the temp module advice given above.

Cheers

Dave

Sorry, I was a bit to quick, did only look at the low temp readings.
Have changed my previous post.

The values should be ~180 ohm at 100^oC.

Your measured values should be approximately like this:

^oC....Ohm.

20....2480
30....1660
40....1140
50....800
60....570
70....420
80....310
90....235
100...180

Thanks for the info

A second thought about your sensor resistance readings...

Both elements shows normal values at the lowest temp, and both drops the resistance quite similar...but with too high res. values.
I doubt it`s a similar fault on both elements (except a problem with the common ground).

I would rather put up a question at your temp measuring euqipment, or the way heat have been applied.

Are you shure that you got the same temp through the sensor metal body, and not only on the surface?

A stable source for checking temp sensors (and be shure that you get the temp all the way through) is boiling water.

Just my thoughts.....

Hi Inge K


Well, to answer your question with some info.

I used to evaluate electronic equipment for a living 10 years ago, and prior to that worked in a repair center of the same for many many years for a very large US company but was based in the UK. I did the testing under reasonably controlled conditions but I folowed the guidlines laid down in the trouble shooting guide at the portal as advised earlier in this thread.

The meters I used were no longer in calbration but were decent Flukes, not the same model but both LCD digital units

The earth connection common I obtained via the use of a small G clamp, clamped against the body of the sensor. The meter -VE lead then connecting to this

The temperature measuring was done via a Farnell industrial unit with correct thermocouple attached

Heating was done on the stove in a saucepan of water (but the wife wasn't happy about that)

As stated in the troubleshooting guide it says to place the tip of the sensor in boiling water for the measurement. This is what I did, I did not place the whole of the body in the liquid only about 5 MM or so of the brass tubed ensor part. I did notice though that there was definatly quite a bit of hysterysis going on taking measurements both from boiling point to low, and then back from low back up to boiling point.

Whilst I can't argue with your opinion - there would be no point in asking for one otherwise would there? Besides which, I would not insult your intelegance or offer of help

I was sceptitcal though about the sensor for exactly the same reading changes as you describe. I did try and find the data on this sensor. It has the words BOSCH 943 stamped on it

According to what I found on the web a part number of 0 280 130 032 came up for the K100RS. I dont know if that matches anything at BMW (at this time). I got the BOSCH data for the sensor for that pert number if you want it (its 232KB pdf file 5 pages) but not sure if its against forum policy for posting here. So at this time have not attached it. If you want it and its OK to I can attach it if it will be of any use (thats if no one has it already). No worries if you already have it.

I am not convinced 100% myself that its definitely faulty, appart from that I dont want to spend another £40 (its £28 plus vat, plus post) to find out in case its OK.

I do however think now from what I have been informed here and read here that the corrosion on the aluminium washer is playing a large part in the problem.

To that end I was thinking now of cutting a small 'V' shaped cut with a hacksaw on the flat of the sensor and soldering a piece of silicone covered wire in. That way I'll have a direct earth to the body of the sensor.

At this time the radiator and sensor is still off while I decide what to do

Cheers and thanks for your continued assistance


Dave

dave ...i fear that the sensor is out of "required " resistance swing

but im happy to be proved wrong

i have found that you dont need to have the radiator "pulled" to do the required work in and around there (but does make it slightly easier ) .

i have done much the same as you ,,,,but found that by removing just the right hand lower , and air box, all is able to be accomplished ,,,even better if you have a set of short ring spanners to tighten up the sensor to the stub .

so feel confident about putting the radiator back in and working in the fashion that i have done

good luck "ol mate"

i have found that you dont need to have the radiator "pulled" to do the
required work in and around there (but does make it slightly easier ) .

Hi Charlie99.

Well the radiator is off because 2 weeks ago whilst I was under the bike looking to see if I had corrected and oil weep from the flange after changing the water pump seals (which incidently now I think didn't need changing at all) the bottom hose blew off the water pump and it spewed extremely hot coolant all over my arms and thigh. It was my fault because I did not refill the cooling sytstem with enough cooland. For that stupid elementery mistake I ended up with 2nd degree burns to my arm, thigh, neck and chin. No one else to blaim - exept me. Not making excuses, there are none. Just a senior moment of stupididy.

So since there was now no coolant in the radiator and since I had never ever seen the fan come on whilst running this bike in the garage I thought I would investigate a little BEFORE refilling the cooling system again. When I pulled the sensor the rest is in thread above and that's where I am now.

It is strange that both the elements in the sensor actually rise and fall together, and indeed I would agree with Inge K that the 'common' conection would apperar to be the culprit. I'm just a little loathed now to spend yet another 40 quid on this thing because its not a perticular pretty looking thing as its an insurance write off cat C. It has no fairings at all. I never purchased this bike to restore it. I think it it to far gone for that. It is just something to knock about on thats different to my other bikes.

However if that's now the opinion of two of you I suppose I'll have to bite the bullet or get shut. I wouldn't mind if I knew for certain the rest of the bike was good but I dont as I've never ridden it, it came in the back of a van. TBH I'm now tempted to break it and put it back on Ebay where I got it from.

I suppose I should have done my homework before bidding... But the engine was described as 'sweet as a nut' Yeah right!

Fuel tank had a leaking seam - epoxy that. seems to be a good fix
Ignition switch duff - replaced (couldn't get the rusted screw out of the side)
oil leaking from the weep hole - seals replaced
Battery is way to small. Has a YTX12 on it, a 12AH instead of a 19AH (yet more £££ to come)

Its 100% better now than it was, but it seems to be going in the direction of a money pit

OK Charlie many thanks for the info. Will think further on this.

Cheers

Dave

One more thing...
The pull the air box.... I can't even get the blinkin air filter element out! ha!

About sensor resistance readings: after I did see the values....and think two more times, I was courios about how the temp was measured and heat applied.
Now I know, no doubt about that part was correctly done.

Since the readings is to high, it would probably run a bit rich...but the most negative is that the fan won`t start.

Since you don`t want to use that much money on this bike, you could add a resistor in paralell to the sensor and hopefully get closer to the correct values at operating temp.

As a reference....the fan should start at 103^oC +/- 3,5 which corresponds to 175 ohm +/- 10%.
The warning light should show at 111^oC +/- 3,5 which corresponds to 143 ohm +/- 10%

About the PDF file...that one could become useful...I`ll PM you my email adress later on.....thanks.

OK no problem will send you the pdf file later on, its only a small file

As I pointed out earlier, there is some hysteresis going on with this sensor in that it does not react immediatly to the given temperature. I'm tempted really tempted now one more time to bring it up to boiling point and leave there until the readings 'eventually' stop and see if it ever does reach 180 ohms. See how longit takes. I'm also tempted to put as much of the brass body tube into the water as I can get. I might me clutching at straws here, but on the other hand I just might have a very slow reacting sensor; - not normal or not.

It isn't that I don't want to spend money on the bike. But I seem to have a very neglected machine here with a myriad of common faults. One other issue I didn't mention was the radiator was also looking like a sieve when I got it. (I patched thtat)... the purists here will gasp in horror but one has to make do sometimes. I purchased another rad off ebay which the seller advertised as off a K75. He neglectd to tell me that he also had a K100 he could have measured it against. As I found out when it arrived.... it didn't fit - too narrow. Well actually I could have got it on but the hoses were all squashed. Not nice.


Dont want to frig it with resistors really, besides which it will involve adding a lower value, not sure what thats going to do to the mid range readings.

No worries, I mull it over and have another play. Will post the file when I get your details


Cheers


Dave

neglected maybe the reason dave .....these machines have lots left in them ......try looking for parts on similar aged jap bikes ...

most often owners not arare of maintenance issues or just oblivious to normal service work ,,and or lack of interest left in them as their riding habits change .

keep at it mate, the prospect of another 20 years is not unfathomable , but you do need the passion to restore the things that need doing ,,,,, be prepared to accept minor specifications and absorb them into acceptable expectations ie 12 amp hour battery ....will do the job ...all things running well ....given start issues ...might come up short ,,,but for me, totally reliable start within 0.5-2 seconds peak demand

Yes agree on the demands of the battery. I only just recently traded a Honda F6C (known as Honda Valyrie in the US) and other bikes too in for a new FJR. The F6C which is basically a cut down GL1500 goldwing without all plastics and an extra 4 carbs only had a YTX12 battery on it. a 580W alternator too. Heavy on batteries, theyonly last about 3 years or so but that battery manages to turn over a 1500 cc 6 cylinder bike with ease.
I guess I just expected the bike to be in a little better condition that it is. Unfortuantly I'm learning the hard way that not everyone is as honest with the truth when it comes to selling as myself.

OK you talked me into it for now.............

Will either try and do a little more testing and if still doubtful tomorrow later on, I will order a new sender from Motobins.

but you do need the passion to restore the things that need doing

I dont have any issues in doing maintancence, in fact I prefare to do all my own where I'm capable
I'm also now thinking of the splines, clutch and gearbox issues that may come my way



Cheers


Dave

Dirk Digler wrote:OK you talked me into it for now.............

Yeah, Charlie have done it, again

Another K is saved.

You get all the help you need right here.

Inge K. wrote:

Dirk Digler wrote:OK you talked me into it for now.............

Yeah, Charlie have done it, again

Another K is saved.

You get all the help you need right here.

OK for now..............

I said I would do a little more testing then get a sensor and this is what I got



This is how I heated the old sensor in the pan of water this morning












This is what I got this morning when in the pan for 3 to 4 minutes or so below...





I then called my local car accessory shop this morning on the phone and got them to cross reference the part number 0 280 130 032

This sensor it appears is used on a lot of European cars like Opel, Volvo, Saab, Jaguar, Daimler and a lot more.

They cross referenced it to the following part number.....VE375050F which maybe their internal number.

4 hours later they supplied me what they say is the same sensor (equivalent) as the Bosch one








I then did the same test on the new sensor, and this is what I got below...



So not a lot of difference there between a new cross referenced one and my old one, appart from the sensors being more closer in value

Surely there must be some sort of +/- margin to allow for tolerance?

Think I might put this new one in and see what happens

The only other thing that puzzling me is how to refill the cooling system on this bike

I read here of leaving the rad cap off until the stat open then squeeze the bottom hose to purge the air out.

Is that the recommended method for this bike?


Note: the meters are reversed on the last picture but they are extremely close to each other on ohms when taking readings.

Cheers



Dave

I`m quite surprised about your readings on the new sensor, newer had any issue with this sensor....only have the info about what it should be.

The tolerances is quite wide....if you look at the values Ì`ve earlier provided on the fan relay......but not that wide...

About filling the cooling system: the metod I`ve used without any problems when changing the coolant is.........fill the system slowly through the cap...when you see the level at the bottom of the filler hose...squeese all hoses, air escapes.....repeat this untill the system is filled.

Fill the expansion tank to the normal level, refit the rad cap.......run the bike untill the fan starts a couple of times.....let the bike cool completly down, remove the rad cap, and replenish (if needed).

Inge K. wrote:I`m quite surprised about your readings on the new sensor, newer had any issue with this sensor....only have the info about what it should be.

The tolerances is quite wide....if you look at the values Ì`ve earlier provided on the fan relay......but not that wide...

About filling the cooling system: the metod I`ve used without any problems when changing the coolant is.........fill the system slowly through the cap...when you see the level at the bottom of the filler hose...squeese all hoses, air escapes.....repeat this untill the system is filled.

Fill the expansion tank to the normal level, refit the rad cap.......run the bike untill the fan starts a couple of times.....let the bike cool completly down, remove the rad cap, and replenish (if needed).

This is what I have always done and I find it usually takes about one refill of the overflow container.

Rick G wrote:

Inge K. wrote:I`m quite surprised about your readings on the new sensor, newer had any issue with this sensor....only have the info about what it should be.

The tolerances is quite wide....if you look at the values Ì`ve earlier provided on the fan relay......but not that wide...

About filling the cooling system: the method I`ve used without any problems when changing the coolant is.........fill the system slowly through the cap...when you see the level at the bottom of the filler hose...squeeze all hoses, air escapes.....repeat this until the system is filled.

Fill the expansion tank to the normal level, refit the rad cap.......run the bike until the fan starts a couple of times.....let the bike cool completely down, remove the rad cap, and replenish (if needed).

This is what I have always done and I find it usually takes about one refill of the overflow container.

OK thanks gents

only.................

run the bike until the fan starts a couple of times

This is what started the whole thing..

I`m quite surprised about your readings on the new sensor, newer had any
issue with this sensor....only have the info about what it should be.

Yes so am I. I suppose its not certain yet all is correct with this replacement sensor until I get the fan working (which it does not)

Speaking of which..... Before I refit and refill the radiator I thought I would delve a little deeper into the relay box under the tank...see if I could check out the fan wires etc.

I opened up the temperature relay/module



This is the temperature module I took apart this afternoon. There is some circuit board blown off.

2 diodes duff, a 1n4007 and a ZY18 18 volt zener are short circuit.


I don't have the 18V 2 watt zener but I have the 1n4007. I may see if I can cobble a couple of values together
to make up the 18v rating for the zener. The problem is its a 2watt rating. The defective diodes are in the pic below






I wonder if this is another common fault, or the result of someone being careless?

Now I know why my fan doesn't work. The temperature sender body was all corroded in the coolant stub
resulting in a bad earth, and I think possibly, someone has been looking for the fault and perhaps shorted the wrong wire out.

Unless I have another gremlin elsewhere waiting...

I'll let you know when/If I've fixed it as I don't yet have a circuit for this module but apart from the chip
which I cant test in-circuit, all the other stuff checks out reasonably well.

Cheers and thanks for the continued input and assistance gents, a big help.


Dave

hmm the 18 volt zenner should be an over voltage protection device , as there is little chance that any such voltage should be present in the bike other wise under normal conditions .

sounds to me like at some stage that the positive ...or earth went high or became disconnected to the battery whilst it was running ,,,and or some back emf ,,,maybe from headlight change beams ,,,could have presented a high voltage accross the system possibly out of the altenator ...maybe even jumpering with another battery ?

or soneone jumpered the fan previously ....but with reverse voltage ? too hard to guess

i would think that the in4007 is sacreficial and the zenner has done its job at protecting the circuit . just a guess as i dont have the circuit either

cut the zenner out of circuit and replace the 1n4007 1n4001 or anything really , make good the vaporised track

and stick it in and see ?

safety would suggest to replace the zenner device at some time (yeah 2 watt version might be a little harder to find ,)

being short circuit it may have saved the ic ? as some of the things used in the electronics are auto specific and more or less one offs durring their run of manufacture ( like the bulb monitoring unit chip, there are replacements but mods required to get it working )

you may have found the contributing factor to the fan not switching on ....good work !

you may have found the contributing factor to the fan not switching on ....good work

I hope so. Looking at the track the feed to both of these comes from the switched contact of that relay. I think it is the load shed relay. That relay is fed via the bottom 15A fuse in the fuse box, so I think your theory is correct. Not so sure I want to leave the zener dissed though. The 1n4007 is in the feed from the switched pin of the relay so its reverse polarity protection, the zener is coming straight of it and as your rightly say its over volts...


I don't have a 2 watt 18 volt zener, plenty of 400mw ones but none at 2 watts. I have large 12volt and a 7.5 volt zeners. I could series them up. Wont look pretty in there and it will be tight for space as they are big zener's. I'm temped... Just hope it hasn't seen the chip off.

Will report back when I do a little more on it.

Edit....

The rad is still off. I was hoping to lower the resistance of the sensor (with a decade box, that way I can see exactly what resistance is required on my bike to turn the fan on) to get the fan to run, but it doesn't with the parts now replaced.

Question...
Do I need the engine actually running ( not just the ignition switched on) to coax the temp module to turn the fan on. If so I'll have to put the rad back to test it all.

Cheers

Dave

Dirk Digler wrote:Question...Do I need the engine actually running ( not just the ignition switched on) to coax the temp module to turn the fan on. If so I'll have to put the rad back to test it all

Power to the heat management relay pcb is feed from the FI relay.
The FI relay relies on the signal from hall sensors or starter button.........so yes basically the engine needs to be running.

To fool the system, you could remove the FI relay and jump the relay contact terminals.
Disconnect the fuel pump at the tank connector, you don`t want the pump to run all the time.

The FI relay have double output, one feeds the heat management relay PCB and fuel pump through fuse 6.
The other feeds the FI ECU, injectors and AFM.

You could also remove the relay from the bike to do your test, it might be easier.

9 = 12V+ to pcb.
31 = ground.
E = sensor.
A3 = ground to warning lamp.
----------------------------------
15 = 12V+ input contact.
A2 = output contact (to fan).

Inge K

Thanks for this. I just hooked the temp module on the bench to a 12v supply (after replacing the duff diodes) using your advice from the above.

I used an RS decade resistance box type 1051 on the sensor input pin E to earth to simulate the sensor resistance and brought the value downwards.

I also connected a meter on ohms to the relay outputs so I could see when I reached the switching points.

To me this does not look good now reference to my sensor actual values.

This is what the resistance was on the decade box for the switching

FAN. (15 to A2) 176 ohms (drops back out at 186 ohms)
Warning lamp (31 to A3) on at 142 ohms off at 149 ohms



These were the values required to switch. I'm guessing these may be OK, I don't know. But... I don't think my sensor may go down to 176 ohms at 103 deg C.

Suppose I'll have to put it all back now and fire it up

comments please?...

Cheers


Dave

.

Your relay functions just as it should now, good work done.
Have a look at reply #26.

Well that's a relief, module functioning OK now according to reply 26 ( sorry blinking buried in this didn't look further up sorry).

So I guess now the only thing to do is put the rad back, refill it and see what happens

Keeping my fingers crossed on this one now, definitely DON'T want a repeat of the last episode.

I just hope that the seals I have fitted I've done correctly and don't leak..

Be a while yet so catch you late as have to swill out the expansion tank, let you know if it all works..... or not

Thanks

Dave


Dave

Well so far so good. It took about at least 20 minutes for the fan to start. I was getting a little worried. Outside temp tonight is 9 degrees C. It only runs though for about 10 seconds or so then shuts itself off. I had it cycle 3 times. I thought I leave it now tonight see if there are any oil/water leaks tomorrow. I put some clean newspaper underneath the bike to catch any drips as a tell tail.

I had a quick look underneath (and boy was it quick), I couldn't see any leaks of oil from the flange or elsewhere so fingers crossed....

I would normally at this time be putting bouncing smiles everywhere, but I'm going to hang on for a while before I celebrate in case it bites me.

But.............. so far, so good thanks to you all.

Bet you lot cant wait till I pull the rear end apart for lube can you

Cheers

Dave

Dirk Digler wrote:It took about at least 20 minutes for the fan to start. I was getting a little worried. It only runs though for about 10 seconds or so then shuts itself off. I had it cycle 3 times.

Congrats with the result , I`m a bit surprized that it seems to function as normal with your sensor readings.

I won`t remember this as the "cooling system issues" thread,......
but the "mysterious temp sensor resistance" thread.

Inge K. wrote:
Congrats with the result , I`m a bit surprised that it seems to function as normal with your sensor readings.

I won`t remember this as the "cooling system issues" thread,......
but the "mysterious temp sensor resistance" thread.

No it's puzzling. But I can tell you that I followed the instructions for testing the sensor laid out in the troubleshooting guide closely. I used good equipment and the testing was done accurately.

I'm thinking now maybe it has something to do with the antifreeze. Doesn't it raise the boiling point of water? Maybe one should use the coolant from the radiator. I used ordinary tap water. Unless of course others have used the 'stated' method before and got the readings you say I 'should' have got. I just don't know to be honest.

However, testing the module on the bench after repair you saw the results and confirm it was working correctly after I posted my results with the decade box; and indeed, after putting it all back together the fan now works although as I said it took a good 20 minutes to kick in.

I'm just happy now it works, and a bonus the cost of the sensor from the local car shop was a mere £9.60 inclusive of VAT (instead of almost £40). Can't beat that in my book.

I guess I was lucky with this (although I paid a hefty price in injury finding out) , bout time my luck changed. Just hope the rest of it is OK now.

Cheers


Dave

i guess boiling water under presure ...and with glycol would certainly raise its boiling point by a few degrees

and i guess hard to replicate outside the system ...forgot to ask ...are you at any significant elevation ? (which lowers the boiling temperature anyhow )

i must remember your experience ....thanks

a good result

You can raise the boiling point without pressure by adding salt but don't get the terminals in the salty water as that will give crazy readings.
Thats both terminals, one is ok.

charlie99 wrote:forgot to ask ...are you at any significant elevation ? (which lowers the boiling temperature anyhow )

I believe my location is 20 meters above sea level. I am 8 miles east of the city of Liverpool. So only about 10 miles or so from the sea.

I'd be interested to know if anyone else has actually done this resistance measurement test at 100 deg C and if they did indeed obtain the readings specified that I should have got. I couldn't get near them, yet my fan does now actually work albeit after about 20 minutes or so of idling. Yet I read on the forum that around 10 minutes or so is quite normal. But here in the UK right now the temp is starting to fall. Out side temperature the other night was around 9-10 degrees C, and it was quite cold in the garage when I had the bike running. I suppose the other thing that may delay warm up is that it is a naked bike now. No fairings whatsoever and at that time nothing of front of the rad either so I guess it was 'well cooled'. No worries. Its working now and as you say, a good result. So very happy now that I've actually seen the fan run.

Cheers

Dirk Digler wrote:I'd be interested to know if anyone else has actually done this resistance measurement test at 100 deg C and if they did indeed obtain the readings specified that I should have got.

Not that many days ago........post 56 in this thread.

Inge

I wasn't doubting your readings, on the contrary; I'm quite puzzled as I know for sure that I did the testing accurately and that my test gear is functioning correctly with reasonably good calibration. Yet they do not agree with what I was supposed to get.

But... in that thread the gent does say..

Have an old analog ohm meter will have to go and get a digital to get more precise

I spent my apprentice ship in the old analogue days. there are meters and there are meters. I still have an old AVO model 9 from my very early days, but I'd rather put my trust in a Fluke these days.

Still as I said, its working now with your help so happy

You asked if anyone have done this resistance test, the thread I did post did just dropp into my mind...since it was not that long ago.....nothing more than that.

I`m quite shure that more info is found out there somewhere with some searching.

But my impression is that most just changes the sensor, without any extensive testing.