EWS Warning- What Else to Try Before The Scrapheap

[Watty100]

My 2007 R1200GS has the dreaded EWS failure message on the dash. 82k on the clock.
The fault occurred on going to the bike in the garage, last time out it ran perfectly.
It also lights up the headlamp and there's no neutral light when the ignition is switched on. GS911 states it can't connect to the ECU.
I've already run one thread on this, thanks for the replies and advice, one last search for tips on what to check before I have to hand it over to someone more knowledgeable than I or potentially scrap it, which I really don't want to do as I've had this bike from new and its part of me.

So Far I have:
Tried a different ring antenna, no change.
Tried both keys in the ignition switch.
It has a factory alarm, no low battery warnings and it does still activate from the remote. It doesn't seem to automatically deactivate with the ignition being turned on, but then I suppose it needs to "see" the correct key is being used. It does deactivate from the remote.
Peeled back the loom, looking for a broken wire, nothing found.
Done continuity tests between the 4 wires from the ring antenna to the smaller of the 2 ECU connector blocks and all 4 wires are OK.
Tested that is power reaching the ECU. The permanent live has 6.7 volts, the switched live gets full battery power, 12.7 volts.
Battery is good and has been kept fully charged whilst I tinker with it.
And finally I sent the ECU for testing to ecu.de who gave a clean bill of health.

So I'm at my wits end where to go next, I don't mind spending some money on an auto-electrician but with the mileage it has it's not worth megabucks.
Any further things to try I've missed out?
Any auto-electrical geniuses out there in the West Midlands area?

 

[Santa-2512]

OK lets go with the ring antenna and ECU are ok.

so you need to look at the other interactive stuff - pic 2

Thats giving you some other avenues to eliminate

Is the bike getting a neutral signal ?

Is the kill switch working and sending the right signal

Likewise the immmobiliser.


have you done the handlebar wobble to eliminate that ?

have your tried removing the immobiliser from the circuit and seeing if that works?

bypassed the gear selector to eliminate that ?

bypassed the kill switch ?

 

[Pukmeister]

Was the ring antenna you swapped brand new?

I have a “new-old stock” spare one I bought years ago as a standby and never used, part number ends in 247 which is the final fix to the long standing issues these components had.

Not much to EWS as I recall, the ring antenna validates the key code and tells the ECU, which disables the alarm/immobiliser and fires up the brains ready to start the engine.

You say the permanent live is 6.7VDC, is that correct or should it be battery voltage eg 12VDC ? Could be a poor termination/high resistance contact somewhere ? I don’t have a wiring/line diagram available to check.

 

[Ian J Hartley]

The immobiliser and the Alarm are two seperate items. It’s possible to completely disconnect the alarm module and terminate the canbus connector with a terminating resistor. BMW part No 61137668405 is a reasonably cheap can bus terminator, allowing for easy plug in. But you can use just a really cheap 120 ohm resister across the canbus terminals. This is really for information, you can try it, but my guess would be your EWS fault will still be present.

From what I can gather, if the Ring Antenna has been replaced and the ECU has been tested off the bike and is serviceable. Then the fact that the GS911 cannot connect to the ECU when it is on the bike and connected, would tell me that there is a wiring fault somewhere.

I would start by going around all the modules that feed to the ECU, disconnecting each in turn to see if there is one that could be faulty enough to drag the whole ECU down.

Good luck.

 

[Santa-2512]

The immobiliser and the Alarm are two seperate items. It’s possible to completely disconnect the alarm module and terminate the canbus connector with a terminating resistor. BMW part No 61137668405 is a reasonably cheap can bus terminator, allowing for easy plug in. But you can use just a really cheap 120 ohm resister across the canbus terminals. This is really for information, you can try it, but my guess would be your EWS fault will still be present.

From what I can gather, if the Ring Antenna has been replaced and the ECU has been tested off the bike and is serviceable. Then the fact that the GS911 cannot connect to the ECU when it is on the bike and connected, would tell me that there is a wiring fault somewhere.

I would start by going around all the modules that feed to the ECU, disconnecting each in turn to see if there is one that could be faulty enough to drag the whole ECU down.

Good luck.

Better explained than i could

2007, my money is on a broken wire

I have a Haynes wiring diaram if you want help with pins etc

 

[Fifth Horseman]

With the information I have to hand, on the BMS-K (engine controller) on the small connector pin 6 with a red 2.5mm cable is the permanent supply, this is connected directly to the battery so should have 12v present. On the same connector, pin 34 with a 0.5mm green cable is the switched 12v from the ignition switch.
If you are measuring 6.7v here the BMS will not be able to operate correctly.
Where are you measuring these voltages between? If you are measuring between the connector terminal and the battery negative, also try between pin 3 (brown 2.5mm cable) and battery negative to eliminate the earth wire as the issue, there should me minimal voltage measured between these two points.
Measuring between the battery positive and pin 6 will show if the live feed cable is the problem - again there should be minimal (less than 0.5v) between these points.

AIUI Neutral light requires a signal from the BMS to the instruments, headlight is driven from the ZFE (chassis control unit) on receipt of the engine running signal from BMS.

As Santa states, a broken wire is the most likely candidate.

 

[botus]

I thought the 6.7v was a ref to the Alarm batteries being OK

GS911 can fake a valve for these but it doesn't seem very realistic or a reliable reading - as 15 year old batteries come out higher volts than brand new good brand replacements - and a multimeter on the batteries gets you yet another set of numbers

 

[Ian J Hartley]

This is the best I can do for wiring information: hope it helps.

 

[Watty100]

Thanks everyone for your help, lots to continue working on there. The spare ring antenna is the new part number, it was a "NOS" bought from this forum.

I think the first thing is to rewire the switched live and restore it to 12v, I wasn't sure if was supposed to run at half battery voltage or not, from what I can gather it needs full power. I did have a very similar issue a few years ago when the exciter wire to the starter motor fell to below 6v, easy fix by wiring it direct to the battery. Maybe that ECU power supply needs the same repair,
fingers crossed
I shall report back in due course...........

 

[Santa-2512]

Before you go running wires, do the simple ( well its not simple)

Strip the loom from the ring antenna back to under the headstock cable ties, that area is notorious for broken / chafed cables. Mskes sense while you have the opportunity


Easiest way is to remove the tank,, your going to need to do that to get to the ecu, s. And check your earth points as well

 

[landmarkjohn]

Hey Watty, feel your pain!
I am in the same boat with a 2008 bike, same diag path as you up to sending the ECU away to ECU.de which I am due to do (last quote I got from them was €320)

All I can add is that I took the ECU out of my known good working bike and put it in the bad bike and got some different results. Can't remember exactly what results, it didn't start but it was enough to convince me of bad ECU. Reading your OP now I am not so sure!

My google trawls leads me to believe that although rare it is not unknown for ECU to fail.

Out of curiosity does your ECU look like it has opened up? Tell tale screw head marks etc?

rereading your post "The fault occurred on going to the bike in the garage, last time out it ran perfectly.".... my bike did exactly the same. It is a bike that would would have been idle for periods of 6 months plus at a time over 3 years in a bone dry factory.

 

[Watty100]

IT LIVES

Well, probably!

I scotchlocked a wire direct from the battery to the red permanent live wire to the ECU to give it the full voltage (pin 6 on the small connector block), switched on the ignition and EWS message gone.
Neutral light back present and correct and headlight not coming on when it shouldn't.

So it looks like that mystery loss of voltage has been the cause all along. Just like the starter issue I mention in Post #9, the wiring diagram shows those permanent live wires running direct from the battery but clearly they go via something that over time deteriorates and causes the voltage to drop.

As the bike is well and truly stripped, I decided to quit whilst I was ahead tonight and will put it all back together another day, with fresh eyes, along with a more permanent, neater replacement for the scotchlock. So I haven't tried to start it as yet but fingers are well and truly crossed that now the EWS message is gone, it should fire up OK.

Thanks everyone for your help, I am truly grateful.

 

[Watty100]

Hey Watty, feel your pain!
I am in the same boat with a 2008 bike, same diag path as you up to sending the ECU away to ECU.de which I am due to do (last quote I got from them was €320)

All I can add is that I took the ECU out of my known good working bike and put it in the bad bike and got some different results. Can't remember exactly what results, it didn't start but it was enough to convince me of bad ECU. Reading your OP now I am not so sure!

My google trawls leads me to believe that although rare it is not unknown for ECU to fail.

Out of curiosity does your ECU look like it has opened up? Tell tale screw head marks etc?

rereading your post "The fault occurred on going to the bike in the garage, last time out it ran perfectly.".... my bike did exactly the same. It is a bike that would would have been idle for periods of 6 months plus at a time over 3 years in a bone dry factory.

John,

Doesn't look like the ECU was opened up, I think they plug it into an electronic rig for testing, you also have to send the ignition key with it as well.

Here is a copy and paste from another thread on here somewhere which led me to check the voltages reaching the ECU, it lead directly to finding the solution above. Hope it helps your situation if you haven't already tried these checks:

Disclaimer: I am no expert. Take the below as exactly what it is: ramblings of a random bloke on t'Internet. It is a pointer to start googling and investigating further. My motive is only to offer info to try to offer some info to help fellow bikers.

So, that out of the way, EWS (Electronische Wegfahrsperre) can come up as an error for many reasons, but thinking logically... Simplistically speaking, the bike key holds a passive "chip" inside it with a code, it goes in to the antenna which [given that the electronic power is there] agitates the key chip and "reads" the code off the chip, sends it to the ECU, which, then, compares it with the stored value and allows the bike to be started if they match. So, components involved : Key, antenna, some wiring, ECU [and indirectly the battery].

So... if the low-beam stays on, there is no whirring from the idle-actuator, no pulse on the fuel pump and no gear indication on the LCD... those symptoms are the same as it the ECU [BMSK-P] was actually completely disconnected. It would then not be illogical to think that the ECU is not booting up. If you can use a multimeter, you can do some basic tests. Head to the smaller of the two ECU connectors under the seat. Disconnect it and do some continuity/voltage tests. If I remember the pinouts correctly (let me know if they are not as expected and I will double-check/correct the post for future reads):

1) Firstly, check that you are getting power to the ECU. You should have the battery voltage [~12V] across pin-3 (-) and Pin-6 (+). (Pin-34 should be the switched +12V [i.e. ON when IGN ON]). The belts-and-braces method is to wire a consumer (like a small automotive (12V) light-bulb) to those to check for the solid current under load.

2) Check you are getting good earth too.(continuity to the frame/engine/battery(=) @ pin 3) may as well check the brown cable going from the battery(-) to the engine on the left side, near the starter.

3) Since you are already at the ECU connector, If you have disconnected the ring-antenna, you may as well check the continuity to the ring antenna; Although that is unlikely to be the problem at this stage, If the theory is sound and the ECU is not booting up at all.
Pins 1234 @ ring antenna should have continuity to pins 8,43,55,57 on the smaller ECU connector, respectively. Numbers are cast into the connector but are very small. Top-tip: Use your phone camera for magnifying if your eyesight fails you in this endeavour.

Ensure that there is no continuity between the ring-antenna connector pins too (in case of cables chafing against eachother)
[You may need some pins to insert into the connectors if your multimeter probes are too fat.]

If all of this is as expected, chances are the ECU has a problem and is not booting up...
Hope that helps someone...

 

[Ian J Hartley]

Corrosion.

My guess would be, based on the age of the bike that the reason for your voltage drop could well be corrosion. If you haven’t already done so, I would remove the backing cover on the ECU connector and check inside. Likewise have a good look at the battery positive terminals.

 

[Watty100]

So, to complete the story, I'm glad to report the bike is now back together and starts and runs like a good 'un. No faults on the dash, neutral light working as it should, headlamp only comes on after the starter button is pressed.

Having found that the fault was low voltage in the permanent live to the ECU, I cut that wire and joined it to a new length of wire direct to the battery +ve.

A simple and dirt cheap fix, I just wish I'd found it before sending the ECU to ecu.de for testing at a cost of almost £100

If anyone reading this is contemplating using ecu.de, by all means do so as they are equipped and experienced in dealing with BMW bike ECU's. I simply filled in their online form and posted my ECU off to them, but I would suggest contacting them first, because I was called by a member of their staff who said if 'd called first and spoken to one of their tech guys I'd probably have been given a few more things to check myself before going to the expense of using their services. You live and learn.........! (and the conversation was in English).

And anyone reading this because they have the same fault, I'd suggest first of all do the handlebar wiggle from side to side, ignition on, and if the fault comes and goes, you'll potentially be looking for a broken wire.
Next, broken wire or not, follow the instructions in Post #13 above. Once you have taken the bodywork and tank off your bike and have access to the ECU connectors and ring antenna wiring connector, those continuity and voltage tests will take 10 minutes tops and hopefully diagnose your fault quickly and easily.
With thanks to UKGSer Abraxas for that information in another thread, and to all who assisted in this thread.

 

[Headtester]

Brilliant news, I like a good ending.

 

[Pukmeister]

Glad you sorted it, I had a hunch the ecu needed a 12v feed (post #3), just a shame about the £100 getting the ecu tested but you live and you learn I guess.