Motronic 2.4, 2004 R1100S comms trouble

[HECOJohn]

Aloha,

My GS911 works perfectly on my R1200RT so I know it's working.  I have an R1100S that stopped working and using the GS911 on the connector I get no information.  The GS911 reports trouble communicating and to check battery voltage.  I have charged the battery and tried again.  I can get by that message and do get a proper identification of the Motronic 2.4 bu, no other information.

My question is, is this the kind of message I could expect with a bad ECU?  I'm not asking to troubleshoot the motorcycle just to help me identify a potential comms problem between the ECU and GS911.

Thank you for your time,
John

[StephanT]

I've asked John to post this on the forum, as I'm sure between all of us we can help him figure this out...  AND it might just help some other people in the process...

@John:
1. when you have your GS-911 connected to the R1100S, what are the voltage readings in the bottom right hand corner?
 
2. when you do an Autoscan, what information is shown? if anything, pls post an autoscan

3. with the GS-911 plugged into the bike, go to Tools -> Setup -> [Test interface], and post the result

once you get back with the results, I will give  acbrief description of what we can deduce of each...

best
Stephan

[Haakon]

I hope this is the start of a GS911 "faultfinding" section?

I am almost sure I would have missed the "bottom right corner" voltage reading :-)

[Jughead]

Hi John

Check the small black wire connected to the starter.  This is often a problem on the 1100/1150/1200s.  It is the small spade connector that either corrodes or vibrates loose.  A cautious squeeze with a pliers will close the connector a little and make for a better fit ensuring a better connection.

[HECOJohn]

Aloha all,

Thank you Jughead, I will check the spade connector.

I'm traveling and not able to get back to work on the bike now to test these things.   I will report when I have the rest of this answer.

Haakon, this is exactly why I have to go back.  I missed all of this information.

Thank you all,
John

[HECOJohn]

Aloha, back in business.

VBAT: 2.23 while volt meter reports 12.09 at battery terminals.  Voltage reports are  All lights shining brightly.
VIGN: 0.00
Firmware: 1303.3
Autoscan: not listed as option.

I'm now thinking it's not a comms issue but power to or through the ECU or ECU it self.  I'll keep looking but, any thoughts?  Anyone think of a reason there would be low voltage through the controller to the GS911, other than a bad controller?

John

[HECOJohn]

Aloha,

Correction, Autoscan show no communication with controller.

[Haakon]

Happy New Year!  Maybe not so "happy" with a no working R1100S :-(
My bet it is some sort of bad connections or wiring.
What year (model) is the bike?
You never told what happen when you turn on the ignition- or how the bike is not working?
Does the instrument panel light up, do the instruments work and so on?

I am not familiar with the R1100S model but my first guess is NOT a faulty ECU.
Could you borrow a ECU from another R1100S? Just to make sure.
(I did find a R1100S ECU on ....  priced at 220$)
Good luck, Haakon

[HECOJohn]

Sorry all, didn't fully describe the problem.

It's a 2004 R1100s.  Build date is 1/2003 and first sold 4/2003.

I purchased the bike for about the cost of tires and brakes not running, so the the price was right.  The story is anecdotal but verified by the currently registered, the safety inspected, and confirmed by the owner of the shop it was in.  "It just stopped running".  It was in a 3rd party non BMW shop where the mechanic incorrectly guessed at and replaced HES.  Next guess was the ECU, but more $ than the previous owner wanted to spend so he sold the bike.

When the key is turned on, the ABS cycles, all lights on, oil pressure and ABS alarm lamps on, normal as far as I can tell.  The fuel pump does nothing.  Pressing the starter with the plugs and injectors out produces good engine rotation and no spark or injector spray.  GS911 reports as stated in previous post.  A fairly intense cleaning and inspection reveals a very clean bike with no obvious conductor damage, blown fuses, loose ground lugs.  I did not pull all connectors apart but the turn signal, ECU, fuel pump plugs look very clean.

I am arranging for a test ECU to validate.  More to follow.

Thanks all,

John

[HECOJohn]

Aloha again,

Okay, new ECU installed, no joy.  Hmmm.  Still getting low battery voltage.  It's an electrical issue and not GS911 comms.

Time to thrash through the terminations and conductors.

Again, thanks all who helped!  I will let you all know what I find and hopefully save someone else the troubles.

John

[schuppi]

Aloha,

Correction, Autoscan show no communication with controller.

Hi John
did you ever controlled the motronic relay and the incoming cables , connectors. maybe the ECU is not under any voltage?
Just a wiring diagram will help you.

[HECOJohn]

Aloha,

The GS911 is reporting incorrect VBAT OR it takes voltage from a different source than shown on the diagram.  Termination 6 on the Diagnostic Plug shows battery voltage using a volt meter.  GS911 still showing ~5 volts.  It does change slightly between key on and key off 9 (most likely headlight dropping battery voltage), never the less, it's not what the volt meter is showing.  When I jump the fuel pump relay to power up the ignition circuit, I get correct reporting from the GS911 on VIGN.

I've narrowed it down to the fuel relay control circuit.  The ECU is not grounding the fuel pump relay coil.  Jumping the fuel pump side fires up the ignition and GS911 reports battery voltage at VIGN, so, that part works nominally.  Now, getting the relay coil to pull in.  The relay works when swapped with the Motronic relay.  All grounds checked okay for continuity to the ECU plug.  Don't know what's going on inside the ECU.

Question:

1. Does the GS 911 get VBAT from terminal 6 on the diagnostic plug?
2. My ECU got very warm (~100+ degrees F) within a minute or two of powering up the bike.  The heat was from the upper right hand corner viewing it from the side marked MOTRONIC.

Still working on it.  Game on now.  Will report when I find something.

John

[schuppi]

Hello
1. Does the GS 911 get VBAT from terminal 6 on the diagnostic plug?  YES, so it is. Down from fuse F5, with a connector in the cable
harness.
Try to connect a new cable to the motronic relay.
2. My ECU got very warm.  That are 38° C, think that is ok. 

[HECOJohn]

Thanks Shuppi,

I'm glad to hear that heat is not a particular issue however after further testing, the temperature went up to where I can't touch it.  Whew!

F5? It's F4 on my drawing and testing proves that out.  Anyway, I get battery voltage with my tester on ter;minal 6 on the diagnostic port.  VBAT on the GS911 returns 5 or so volts.  Still 0 VIGN.  Autoscan is still a no comms with the ECU.

Without a diagram of the ECU, it's a painstaking process to try to map this circuit.  There must be a short somewhere in the external wiring causing this but, without the diagram, it's a search and destroy mission.

I'll keep on it.

John

[schuppi]

Hi John
Sorry, that was my fault. Just took a diagram from R1150.
But here it is.  http://www.s-boxer.de/vbglossar.php?do=showentry&id=56

please look for the cable connector down under fuse F4, marked with 30A4. Maybe you have to disconnect all the red/yellow cables and install new cables for the relays, ECU and diagnostic plug.

Good luck