96 K1100LT 0302263  I have done some testing and here is what I have found. At the fuel pump relay checking voltage across #8(blue wire with brown stripe) and #10 (green wire with yellow stripe) I am only getting 4.2 volts it goes up to 5v when I press the start button. What would keep it rom getting full voltage?

Someone has been messing with your wiring there should be a blue/brown and red/green. the green/yellow has been put there to bypass the sidestand switch I would say. If this is correct the g/y should have unswitched 12v all the time and the control is via the b/br wire.
The g/y wire gets its power via fuse 6 so that fuse probably needs to be replaced.
This fuse allocation will be handy to laminate and store in the tool roll.

Thanks for the fuse allocation, yes I will keep a copy of it on the bike.
Green / red stripe is connected to terminal #6 and yes there is power on that wire as well as the green/ yellow stripe which is connected to terminal 10. But I'm still at a loss as to what all is involved with the control wire blue/brown stripe allowing the relay to power up.

What voltage do you read at fuse #1 when you turn on the ignition?
It should be the same as the green/yellow wire in the relay socket.

OK I'm going to keep these two questions together on the same post. Seeing how I'm not sure which direction I need to go first. Why I'm questioning the ECU is because I bought it used of line from Stockers motorcycle parts, when I ordered it I was told that it came off of a 96 K1100LT.  Acording to BMW dealership it is an aftermarket part. Are ECU's known for causing problems? If not why would there be an after market part on a 96 bike?

Back to fuel pump. With the ignition key on I have power to the red/green and the green/yellow. I do believe that the blue/brown is the control wire but not sure as to where it is being controlled from? With the side stand down the bike will not even turn over so I'm assuming that the side stand switch is working properly.
Power on each side of the fuse are the same.

Best to post a photo of the ECU as I have never heard of an aftermarket ECU for a K1100 although Power Commander did have an extra that pluged between the ECU and the harness.
The engine should turn over on the starter with the side stand down but the switch cuts the power to the injectors preventing the engine firing.  The ECU will have a Blue, green or Orange label in it and the BOSCH name with a BMW part number. It lies flat under the seat with the multipin plug going into the top surface.

The Blue/brown wire supplies an earth to the relay for 1.5 seconds after it gets power and that is when the key is turned on or the kill switch is turned on when the key on, or when the ECU is getting pulses from the Hall Effect sensor for #2 & #3 coil. You will need to use a multimeter with a needle not a digital meter so you will pick up the needle movement when the earth is applied. I wouldn't be too hasty in blaming the ECU as they have proven exceptionally reliable.

RicK G wrote:The engine should turn over on the starter with the side stand down but the switch cuts the power to the injectors preventing the engine firing.

On a late MA2.2 the sidestand switch cuts the ground connection to the relay coils for the Motronic relay and the starter relay.



Divesh: As you have power to both relay coil and switch, it's only the signal missing which you can test like Rich says.
In the first post low voltage to the relay coil is mentioned....if that still is present (with the other probe to a good ground), check also the voltage to the relay coil on the Motronic relay (same colour code).
If that also is low, the suspected part is the kill switch.

Inge K. wrote:

RicK G wrote:The engine should turn over on the starter with the side stand down but the switch cuts the power to the injectors preventing the engine firing.

On a late MA2.2 the sidestand switch cuts the ground connection to the relay coils for the Motronic relay and the starter relay.



Divesh: As you have power to both relay coil and switch, it's only the signal missing which you can test like Rich says.
In the first post low voltage to the relay coil is mentioned....if that still is present (with the other probe to a good ground), check also the voltage to the relay coil on the Motronic relay (same colour code).
If that also is low, the suspected part is the kill switch.

More info for the aging brain to absorb Thanks Inge

Here is a photo of the ECU that I purchased. Again I was told by my local BMW that is was an aftermarket because of the numbers on it. I sent a photo of my ECU so that they could look at it and possibly tell me if it was the proper fit for my bike. OK I must have the late MA2.2 ECU because my starter will not work with the side stand down.

I will look for an analog meter all I have is a digital one and no one in the area dells an analos meter. One of the disadvantages of living out away from big cities.

Here is another try to upload the photo of my ECU

diveshadow wrote:Here is another try to upload the photo of my ECU

Instructions on how it's done https://www.k100-forum.com/t998-posting-pictures-and-movies

I'm sure that I wil get this soon

That is the early type control unit for K1100 up till 7/93. the part number for yours is 13611464717

So Rick you are telling me that this ecu will not work for my bike or is at least not the correct part for my bike?

That's right. It's for the 1992 & 1993 K1100 and is the 2.1 motronic.
The bozos at the BMW dealer have been drinking their bathwater when they said not a BMW part.
Most of the dealers don't see very much of the bikes once they are out of warranty so unless they worked on BMWs in the 90s they don't even recognize the bits or know how to work on them.

Rick
Thanks for the input because I'm still in a learning process the part you listed is called an ignition control unit correct? Does this unit mount on top of the battery? Also one of the parts place listed it as ABS ignition control unit. I just want to make sure that when I send this one back they dont send me the one mounted on the side of the ABS system. I'm assuming that the one on the side of the ABS is for the ABS system.
 
In defence of the BMW parts man that told me that I had an after market part he is very young and probably just as new as I am to the BMW world.

Also how would I have been able to find out that the one I have is for the earlier models? Is there some site that shows the difference between the two? When I was looking for the part several people listed a similar part but they were not sure of the date of the bikes that they came off of.

Also the parts place that I'm getting the parts from mentioned that there are two different sizes of control units on my bike but I'm only seeing the ECU/ICU and the other one is the ABS control unit.

Looking to limit any further delays in riding my bike.

Real OEM is the best source but don't take it as gospel as I have found mistakes in it, I found one about 10 minutes ago  http://www.realoem.com/bmw/
You can enter tha last 7 digits of your VIN and it will tell you the model etc and go straight to the right page for that bike. You can also enter a part number and it will tell you which other bikes use it.

The ECU (Engine control Unit) sits above the battery and has a multi pin plug that plugs into the top surface, the ECU that you have still sits above the battery but has the multi pin plug on the left side.
On both models of K1100 the ABS control unit (the electronics part)is vertical and on the 96 it is attached to the left side of the ABS controller (mechanical and hydraulic controller).
The K100 and K75 have an ICU (Ignition Control Unit) which is located behind the steering head but a K1100 does not have that item it all takes place in the ECU
This is the correct unit for a 1996 model http://www.ebay.com/itm/BMW-K1100-LT-RS-1995-1100-K-S231-BRAIN-BOX-IGNITOR-IGNITION-COMPUTER-/290688585386?hash=item43ae63ceaa:m:mTysIiq38JEaKlPE7uH4PQw&vxp=mtr

Just out of interest if you do a search on ebay for "BMW K1100 computer" there are some like yours should have, some like the one you have now  and an early ABS control unit.

Don't take too much notice of what the dismantlers tell you.  There is one seller on fleabay yhat has an ICU from a K75 listed as a cruise control unit for K75, K100 and K1100.

I have also heard that MAX BMW in the US has a good parts listing by model.

Hello RicK and Inge

Well I'm back now that I have installed the latest ECU I have 11 to 12v on the green wire going to the tank but still not getting the fuel pump on so I will pull the pump out tomorrow and do a bench test on it but for now here is a pic of the ECU that I was sent. And before I could not get power to the fuel pump at least now I;m getting power to the pump. And yes I;m getting the pulse to the blue wire with the brown stripe.

Well after establishing that I am getting power from the relay I started doing a continuity check on the wiring and all seemed good. Did a bench test on the fuel pump and it works. So I took the pump and the sending unit out of the tank and hooked it up. I have power to the plug but was not getting power to the pump. Kept checking continuity and thats when the positive wire coming from the sending unit dislodged from its soldered point and I could see that it was just barely making a connection. This bike has been sitting in a garage for the past six years, I had already taken the pump and unit out to cleen out the tank but felt that I could just clean the rust off of the sending unit and all would be good. With that much corrosion it was best just to replace the item. So now I wait on the new unit to arrive. So anxious to ride my bike,but I had to settle for a ride on my Suzuki 1400 Intruder. Its just to loud for the neighbors.

The 4 pin plug that connects the tank to the harness is prone to failure. I had both fail on my K100 and K1100 so I replaced them with 4 pin spade terminal auto connectors and have had no more trouble.

Thanks I'll change it out before I put it all back together

You can get a very fine screwdriver in and open the male pins a bit or pliers and close the female ones.
Many have been caught with them because you measure from it both ways but rarely across it when it is plugged together.

Thanks RicK

You have been a tremendous help. I have my bike back together and was able to ride it Friday.
And yes the plug did create a problem, and because I had not gotten the proper wire connectors I was just going to use the original plug until my connectors came in, but as you had mentioned there was problems with the connector so I had to adjust the pins until I get my new connectors in.

I'm adding a few photos of my control module for those who know the bikes well. The first control module that was sent to me would not allow the bike to get power to the fuel pump. So the parts house sent me a different one now the bike runs I have driven it about six hundred miles but is just has no get up and go to it. RicK suggested that I could still not have the correct control module. I have put in a new fuel pump, fuel filter, and spark plugs. The exhaust is running clean.

The different units are the non catalic and catalic. the non cat was apparently used on the authorities (police) bikes and the cat ones were the over the counter version.  Inge K will be able to tell you but I haven't the expertise with the part system to be able to tell.

diveshadow wrote:

A parts search shows this ECU (1341742) is for an R series 1100.
Try one of these

13611464717
CONTROL UNIT MOTRONIC

From:05/13/1993
To:-
Weight:0.639 kg
Price:$1617.48

Supersedes:
13611464649 (03/01/1992 — ), Exchangeable retrospectively
13611464607 (11/04/1991 — 06/17/1992), Exchangeable retrospectively
13611464491 (05/01/1991 — 02/15/1994)

Part 13611464717 was found on the following vehicles:
K589 (K 1100 RS, K 1100 LT)   (06/1989 — 04/1999)

This is the catalytic version

Is there anyone out there that could send me a picture of 97 K1100LT ECU, fuel control module.?

They look the same as the one in your picture but the part number will be 13611464717 or 13617651541 if it came from an authorities model (police)

The unit will look just the same, its the part number you want.
I have a '96 K1100RS and the part number (which you see at the bottom of the label in your photo) reads 1 464 710
This equates to BMW part no. 13611464710 which supersedes 13611464717 which I posted above.

The number on the unit you have starts with 13##### and as far as I could determine from realoem, those units are for the R series not K.

Go to realoem.com and enter your last 7 VIN digits to see all parts for your model.
This is the Motronic unit for your model which is the one I posted above. If you then click on the part no. link (the one at the top of the list) it will take you to more info on that unit like units it supersedes and other models that have that unit. Compatibility appears retrospective and your K is a later model so, I'm not sure, but you may need a later unit. If it were me I'd try any of those I listed above.

Sorry. I can't post a photo of mine from my tablet. New laptop coming any day now.

Hope this helps you to find a suitable unit.

NOTE: the BMW oem part number has 1361 in front of the part number that is actually on the unit.

I believe that the difference between the R and K units is only the software and have been told that BMW should be able to flash the right software to it but I cant be really sure you would need to ask at a dealer.

Thanks so much RicKG and Holister
 I returned the ECU and they sent me one with the number 13611464717 the bike now runs great. The parts house was sure that thier was no different between the ECU for the R series bike and the K series bike ECU. But I'm thankfull they were willing to switch it out for me. If it were not for the knowledge that you are willing to share I would still be stuck with a bike that does not run properly.
Keep up the good work.