Fuel Pump/CANBus Problem

Schtum

Schtum

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My GS died today. It refused to start after I parked it up for about 30 mins. There's no fuel coming from either injector.

It was recovered....yes on the back of a flat-bed recovery truck.....:rolleyes:.....and taken to a friend's workshop.

He writes.....

I need some help with the diagnosis. Here's what I've found so far:

Ignition on, self check OK, ECU happy. Turns over on starter but no fuel pump.

Fuel pump is powered through a "Fuel Pump Driver Module" from the ECU and the CANBus controller (Why can't BMW just use a relay like every other fecker :bang.

Pump itself is OK.

Can't find any power or signal going to the Driver Module from ECU/CAN when disconnected.

With everything connected I can't (easily) get in to measure a signal, however I'm seeing something on the output from the DM to the pump. Not 12volts, but something.

I don't know how the CAN bus works but my initial guess is that the DM is powered +12V through the CAN controller, so that no CAN = no engine, and gets its power earth through the ECU for the same reason. It then gets a separate signal from the ECU - not the CAN - to run the pump as appropriate.

So.....initial diagnosis is....

The DM is dead (I'll come back to why in a minute) and so won't drive the pump. With no DM connected the CAN and/or ECU shuts the thing down anyway so I won't and shouldn't expect to see a signal from the CAN/ECU.

To confirm the diagnosis I really need to know the following:

1 - Should I be seeing 12V at the DM power input when it's not connected or will the ECU/CAN shut it down as I suspect?

2 - Should I be seeing a signal on the signal wire for the DM when not connected? If so what does it look like (I've never poked around a CANBus before). Am I going to have to get the oscilloscope out to find it?

3 - If I make the effort to break into the feed to the DM when its connected what will I see? I suspect I'll see a permanent 12V power feed and some kind of on/off signal from the ECU. Correct?

4 - Anyone seen this before?

5 - Is the DM available as a separate module?



Now, the problem with the Driver Module is.....

It lives in a wee housing on top of the fuel pump mounting flange. It's sealed off from the inside of the tank with a fancy connector and from the outside world with a rubber gasket. The gasket on this one was not installed properly and was poking out. As a result the inside of the housing was full of a mixture of fuel (presumably from inside the tank and/or spills while filling) and water. The fancy connector has been soaking in fuel for so long it was spongy instead of solid (managed to get it off without breaking it, just!) but more importantly the contacts were well corroded.

Theory at the moment is that the extra effort of pushing current through the corroded connectors has proven too much for the DM and it has expired. Sound plausible?

One final question – If I ditch the DM altogether and wire the fuel pump through a relay that only activates on starter cranking/engine running will the ECU and/or CAN bus controller throw a wobbly fit?

Hope someone can help.....:)
 
Sorry can't help you with the signals but exactly the same thing happened to me last week when on holiday in the Yorkshire dales had to get it brought home on the back of an AA truck and am currently waiting for BMW to pick it up from my house. I am 99% certain it will be the fuel pump control module which is at fault. This component has already been the subject of a recall to 04 and early 05 bikes but from what I can find out later bikes are also suffering problems. Who in their right mind would design an electric component that by poor design sits in a pool of water!!!!

I believe the contoller costs just under £50 and if you look on the advrider.com website you will see many complaints about it and even a get you home fix where the controller is bypassed.

good luck
 
Hi Schtum,
FWIW my 2004 bike has been good thus far regarding the fuel pump/controller (touch wood), however my bike has always been garaged. I heard that the pump controller corrosion was due to the bike being parked outdoors on the sidestand, allowing water to pool on the pump controller and corrode it. Does your bike live outdoors perhaps ??

Agreed it is a design oversight by somebody which ought to be rectified. The recall as I remember was just for an O ring recall on the pump as some had been known to leak from build, I don't think the controllers were replaced as part of that recall. IMHO the whole fuel pump controller area needs a redesign to stop it being such a water trap and cause for breakdowns, especially on a touring enduro bike. Even if the ventilated plastic cover over the fuel pump area was redesigned with a water trap/drain beneath the grilled area to let heat out but prevent water ingress and allow drainage, it would help considerably.

I have also had vulnerable connectors on my bikes loom apart from when I bought it nearly new and sealed all the conntectors with silicon grease which may have helped a great deal in keeping things working, especially this pump controller and the rear light and oil pressure switch wiring. I recently had the tank off and checked the pump controller during tank removal and all still looks good.

Hope your bike is fixed real soon mate.
 
it's a classic

The diagnostic dongle would have told you straight away what the problem was- saved me the cost of 1 flat top in Germany and another in Turkey :blast

linky here.... with picture of guilty part and correct gasket
http://www.ukgser.com/forums/showthread.php?t=98586&highlight=1200

same happened to me a few times....
  • clean out the area well
  • fit new fuel pump energiser thingy
  • ensure the gasket is the blue coloured (thicker one)
  • mount it correctly
  • once done spary liberally with thik chain lube all over
  • close the 'dome' cover
  • ...and carry a spare for next time :thumb
 
Even with the blue o-ring, this weakness has made it to my "regular" check routine... As I don't commute on the bike, I go in there after a trip away that involves rain... right after I wash the bike :eek:, I open it up, lift the controller and make sure it's dry... Lube the connectors then carefully close it up... Couple times a year. If I haven't been in the rain for a few days, and just wash the bike (rarely =), I pop the cover off and soak up the puddle...

After reading about a bunch of failures, If I were going on a multi-monther I'd carry a spare one too (or perhaps know the bypass trick). Along with a serviceable micro-switch for the front brake lever.

Having the tools and knowledge to do your own repairs saves a bunch of waiting around on the side of the road for rescue.... Last year in Norway, a Ducati owner spent 9 hours in the rain (in the cold, at the top of a pass) , then almost as much time as the rest of us to get home... all of it waiting for roadside assist to make things right... (we got texts all the way home...)

I'd rather be busy trying to fix the problem IMHO...

Al...
 
Hello Schtum

My bike did exactly the same, on holiday in the Alps, on Sunday. Actually,it starte dplayign up on Satirday and was intermittent but getting steadily worse until it evetually packed up. Fixed by the local dealer on Monday morning for 150 Euros. (Taken to the dealers by Carole Nash's European breakdown service.)

A quick search on here shows it's obviously a common problem. As there is no sign of the design being changed by BMW, I think I'll be buying a spare to carry with me on long trips. It shouldn't be necessary, I know, but it would have saved me a whole load of waiting around.

I'll write to BMW to see if they're prepared to do anything - the bike is two months out of warranty - but I'm not holding my breath.

Now for the silly question - can someone tell me where I find this offending part on the bike so I can slather it with something to keep the water out?
 
Well it's fixed now. I have to say that my good friend Dave, aka greenVFR, deserves a great deal of credit and another HUGE thank you from me.

Within 20 minutes of us getting the bike of the recovery truck it was on the ramp in his workshop with the tank off and the fault was pretty much diagnosed.

Further research on the 'net last night and today confirmed that it was a known fault for which there had been a recall. However, my dealer said that my frame no. was not within the range of the recall..... :nenau The fact that the dealership keeps the DM controller for the fuel pump as a stock item is pretty telling though. £50 later for a new DM controller and the bike's back together and running, although we haven't had a chance to road test it.

The service guy in the dealership has also submitted a warranty claim to BMW for the part, in spite of the fact that the bike's 6 months out of warranty.
 
A smidge of dielectric grease over the components won't do any harm!
 
Well this is what mine looked like .............. :monkeypiz
 

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On the lhs of the bike as you`re sitting on it look where the beak meets the fuel tank cover. If you look directly below it you should see a cover about 3" diameter with slots in the top & some wiring going into it from the rhs through a hole. The fuel thingy lives under this :thumb I taped the slots in mine over with electrical tape as while the bike is in forward motion I imagine enough air is getting blown round that area through the hole that the wires come though to keep it cool.
 
Thanks John & Bazza - now I know what it looks like, but where actually is it? :hide

Is it in a position to be sprayed with Silicon? Can you get at it? I presume if water can get up there to kick off a corrosion process, you can (somehow) get access to it without taking half the bike apart??:nenau

Sorry for asking a dumb question but I'm a bit of a numpty when it comes to anything remotely technical - hence my paranoia about prevention 'cos I suspect cure will be outside my capability! :(
 
Peter Pan said:
Thanks John & Bazza - now I know what it looks like, but where actually is it? :hide

Is it in a position to be sprayed with Silicon? Can you get at it? I presume if water can get up there to kick off a corrosion process, you can (somehow) get access to it without taking half the bike apart??:nenau

Sorry for asking a dumb question but I'm a bit of a numpty when it comes to anything remotely technical - hence my paranoia about prevention 'cos I suspect cure will be outside my capability! :(
Click to expand...

It`s easiest to get to by taking the side panel off as in Bazzas pic but make sure you get the front clip thingy at the bottom of the panel back in properly as it`ll peel itself back when you`re riding :augie
 
Have we informed BMW ?

With respect,

Can we please inform the people who design, manufacture and sell the bikes / equipment we spend thousends of our hard earned pennies on, or nothing will improve.

It will be easy for BMW HQ to reply

"Nobody told us"​

If we do not let the powers to be, no of the problems that arise with our "Prized Possessions"......nothing will change

.......................post it to them.
 
Reason I got rid of my 1200GS - this is totally unacceptable cheap shit design and not worthy of anything bearing a BMW badge.
 
Nippy Normans supply Touratech, Wunderlich, Desert Fox and many other makes of accessories.
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