K1100 early 1993 wiring with motogadget m unit

[Lucas1983]

Hello everyone,

I am in the middle of a cafe racer build.  Trying to finalize my wiring diagram unit m-unit.  However, since it an early 1993 (production late 1992) it is a bit different from any wiring I was able to find on this page.  There was one for 1994+ but with the 1993 model I have to deal with Ignition output stage as well.  I have clymor manual but motronic cables for the 1993 model are not color labeled like they are on the following page for the 1994+.
I think I have most of the wires figured out except for two.  The Red/yellow cable that went from fuse box to motronic and motronic relay.  and the Green/black that went from motronic to motronic relay/ clutch switch.  I found the motronic schematics on this page but these are beyond my elctronic knowledge without color coded wires.  Red/ yellow went thru fuse box so my instinct tells me just connect back to power straight from battery.  I am not sure what to do with green/black.  Since it went thru clutch switch I would probably ignore that one.  Any input is greatly appreciated.  Thanks.   

[Laitch]

A key to wire color-code abbreviations on the 1993 schematics is on the last page of the diagrams found on a link in this post.

[Lucas1983]

Thank you Sir.  Once I am done with the wiring diagram, do you think you can take a look at it?

[frankenduck]

Here's the BMW wiring diagrams for a US 93 LT all in one PDF and labeled in English:

http://www.kbikeparts.com/classickbikes.com/ckb.tech/0.ckb.tech.files/kwiring/K1100LT.93/1993.K1100LT.Wiring.SLP.V2.0.pdf

[Kaos]

Thank you Sir.  Once I am done with the wiring diagram, do you think you can take a look at it?

Id love to.
Even tho the 94 has different colours the most important ones have the same colours
Do you know if you have a v2.1 ecu or a 2.2? Because those colours would indeed be different

[Kaos]

Also this post: https://www.motobrick.com/index.php?topic=15838.0 contains a colour coded wiring diagram for 4 valves, adjusted for usage for the m-unit. You can Use it as a guide so you wont have to reinvent the wheel

[Lucas1983]

I believe I have a v2.1 ECU.  my wiring diagram attached.  Two wires in question are bubbled.  However, after reviewing the motronic schematics provided by other members I think I have it right.  I think. 

[Kaos]

I believe I have a v2.1 ECU.  my wiring diagram attached.  Two wires in question are bubbled.  However, after reviewing the motronic schematics provided by other members I think I have it right.  I think.

Power is indeed red/yellow comming from the connector.
Green black is indeed suposed to connect to the m-unit ignition.

Questions:
Is your ignition switch 2 or 3 wired? Usually its ground, power and start wire (which goes into the lock)
15a fuse wire, are you planning on connecting it after, before or separate of the 40 a fuse?
The M-unit fuse cable (from motogadget itself) is 6mm2 which is for max 40 amps.
Alternator blue wire has currency, why does it lead to an output?
also when the fuel relay is fed by a battery cable, I would personally divide the green browns from aux 1 over aux 2 both outputs. Fans can draw higher voltages leading to errors this helps with the spike.
do keep in mind, this is not a must and totally up to you.
Also the k-neutral requires a 12v, you could set that one up in an aux output.
If i do recall correctly the maximum current on inputs are 0.01A and wont be sufficient for your k-neutral connected to the lock wire, instead of the power or ignition

Good luck wiring. Its a tedious job with trial and error. and do keep asking.

[Kaos]

I believe I have a v2.1 ECU.  my wiring diagram attached.  Two wires in question are bubbled.  However, after reviewing the motronic schematics provided by other members I think I have it right.  I think.

If you have a starter module and a co-potentiometer its a 2.1.

Also I see you have an Oxygen sensor?, the one thats used in the exhaust system?

Topping it off, the part where you drew the ign. output stage will just be the blue/black cable coming from the loom.

[Lucas1983]

Actually I do not have co-potentiometer.  It is a US bike. So I guess it is a 2.2 version.  I have a 02 sensor but apprantly I do not need it.   Apparently bike will run rich a bit richer at ideal.

the blue/ black I thought goes to tacho.

Ignition is just a place holder for now.   Probably m-lock.

15 amp fuse - originally it came from fuse box with 15 amp fuse so  I kept it.  Now that I think more of it, can i just tap one of the start outputs on the m unit?

Blue wire from alternator.  Good catch. originally went to dash light inidcator.  Iwould probably just remove that cable?

Fan relay - so two separate green/brown for the two outputs on the Aux 2?

k neutral - so instead of going around to ignition with 1amp fuse, just connect straight to Aux 1?  makes sense.

Thank you for the hep on this one. 

[Kaos]

Actually I do not have co-potentiometer.  It is a US bike. So I guess it is a 2.2 version.  I have a 02 sensor but apprantly I do not need it.   Apparently bike will run rich a bit richer at ideal.

On which side of the ecu do you plug in the wiring loom? Top = 2.2 side = 2.1
With 2.1 you do need both the starter module and potentiometer, oxygen indeed not so much.

the blue/ black I thought goes to tacho.

Correct, but what i ment was, its just the bleu/black cable sitting within the rest of the loom.

Ignition is just a place holder for now.   Probably m-lock.

those are handy, remember brown goes into the lock, red is power which u can use to connect the k-neutral on.
Dont connect the k-neurtal to (brown) cable that goes into the lock.

15 amp fuse - originally it came from fuse box with 15 amp fuse so  I kept it.  Now that I think more of it, can i just tap one of the start outputs on the m unit?

Well yes, but then you have to feed the fuelpump from aux 2 [10a per output, needs 7.5], then the fuel relay becomes obsolete and draw a powerline from the constant 12v (battery cable connection on the m-unit) to the red/yellow for the ecu.

Blue wire from alternator.  Good catch. originally went to dash light inidcator.  Iwould probably just remove that cable?

absolutely not. Then your battery wont charge. Its your charge indicator. I've seen people replace the oil pressure warning light with this one or a small headlight bulb under the tank.
I personally use the tacho warning light for it, but you have to check if it can handle 12v, most are 6 i do believe, then it needs an resistor.

Fan relay - so two separate green/brown for the two outputs on the Aux 2?

not persé, it would be handy to prevent startup overdraw but aux 1 should be sufficient.

k neutral - so instead of going around to ignition with 1amp fuse, just connect straight to Aux 1?  makes sense.

that is one of the possibillities.
start input of the m-unit only provides 0.01 amps to complete the circle for input buttons, letting itself know it should act.
But the power comming from it wont be enough to power the k-neutral.
Options are aux, ignition (not the best choice) or the powerline used for the lock (slot 30 on the relay of an m-lock with 1amp fuse)
But then, you cannot keep putting every thing in aux since they have a combined amperage of 30. Choices.

[Laitch]

There was one for 1994+ but with the 1993 model I have to deal with Ignition output stage as well.

Actually I do not have co-potentiometer.  It is a US bike. So I guess it is a 2.2 version. I have a 02 sensor but apprantly I do not need it.

According to BMW's Motronic 2.1—2.2 manual, if your Brick has an ignition output stage it is a Motronic 2.1. In the 2.2 models, the coils are operated directly by the Motronic control unit. Maybe a previous owner stuck a muffler with an O₂ sensor on it. It's seems like you already have some kind of hybrid. Maybe my manual is a grey market issue. 

Kaotic for sure, but you seem to be adapting.    

[Kaos]

Kaotic for sure.

 

We've established it's a 2.2 due to lack of the co-potato meter and the ignition module.

Also the simple question "where do you plug in the wiring loom" establishes it quite easily.
The o˛ sensor could be a state thingy for US bikes for what i've understood, something with California laws and stuff
But meh. Not really that important.

[Laitch]

We've established it's a 2.2 due to lack of the co-potato meter and the ignition module.

You must be using "We" in the strictest sense.    To clarify: Lucas indicated it had an ignition module but it actually doesn't have an ignition output stage? Early 1993 models have them. Was it removed? Was the Brick imported into the USA? Was his VIN-checker information incorrect or did he just enter data incorrectly? "Where do you plug in the wiring loom" seems like a simple question. Where did Lucas answer that one?

It's been decades since I've been in actual Kaos, which wasn't much fun for the most part. This type is recreational!

[Lucas1983]

I thought I had 2.1 version but after speaking to Kaos we established it was in fact 2.2.  ECU plug is on the top and I do have ignition output stage.  I do not have co potentiometer.  M unit came in yesterday and I will be starting bike today for the first time after re-wire. I will keep you posted guys.  Again thank you for all the help.

[Kaos]

Glad you find it amusing, as do I.
Should have borded the forum way earlier.

Answer was "in the top" Lucas also insured me that there is no co-potentio, or start module/output stage.
I just hope it didnt get lost in translation. What I was after is the cooled starter unit connected to the loom.
If its absent, its 2.2.

We was indeed in the stricted sence. Bro slid into my dms for the proper thirst trap I am

[Kaos]

and I do have ignition output stage.  I do not have co potentiometer.

Do you have this unit, yay or nay?

4831050_Product.jpg (16.34 kB . 768x511 - viewed 52 times)

If yes, then this should be present

images (3).jpeg (3.85 kB . 260x194 - viewed 53 times)

Not having and missing are 2 different things.
Do please us with a pic of your unit just to be sure.

Also no need to get scared. Most wires will still be the same
I have a secret stash of all ecu wires and where they should go.

[Lucas1983]

I have the the first one, ignition stage output, but I do not have the co-pot.. I know because I took entire bike apart lol.  Maybe a previous owner removed it some time ago, or…
I thought that once your bike has the o2 sensor, which is most U.S. market bike,  you do not have the co-pot.  At least what I read from some posts.

[Laitch]

I have the the first one, ignition stage output, but I do not have the co-pot..

Yay!    You're in 2.1 territory, Lucas. 

Let's pretend none of this matters and move on. 

[Kaos]

Do you have this ecu

Screenshot_2024-10-26-19-54-55-82_40deb401b9ffe8e1df2f1cc5ba480b12.jpg (57.61 kB . 768x559 - viewed 51 times)
Or this one

images (4).jpeg (4.96 kB . 259x194 - viewed 51 times)

In case of the first, your wiring diagram can be as we discussed in the private messages

[Kaos]

Yay!    You're in 2.1 territory, Lucas. 

Let's pretend none of this matters and move on. 

Weird top tho.

[Lucas1983]

I have the first one. The one with the green label. I guess I confused you kaos when you asked me if it was the top connection.  Sorry about that.  Ecu was mounted vertically to the battery so I assumed ‘top’.

[Kaos]

Fair, good thing i live by the name.
Anyway. Nothing will change for you and the way we mapped it out.
And for backup you can check the diagram in the provided link.

[Lucas1983]

Happy to report brick started on a first try with the new wiring. Thank you everyone for your help. I have one more question,  very small one in a grand skim of things, but I have an issue with the kill switch lol.
I am using a switch from cbr1000rr and no matter how I wire it, the kill switch works in reverse.   My guess is I have to reverse polarity inside the switch. Diagram attached. 

[Kaos]

Well, you'd have to inverse it with a relay.
As this set up is letting the m-unit believe your kill switch is completing the button circuit
Nifty trick, you dont have to use a kill switch. Double tapping the start button will also function as a kill switch.
Motogadget magic.

Writing this made me doubt myself, so Not sure if its only mo- button functionality or general.
Try it anyway.