Fuel gauge on my 09 GS has decided not to work

The fuel pump return flow drives a venturi (aka ejector) that sucks fuel from the RHS over to the left. The fuel gauge sitting on the left spends a long time around 1/2 full as the left is kept topped up. The level then falls quickly as the right side is now dry. All features of the tank shape.

The fuel strip is Mylar plastic with printed copper tracks. It all sits inside a hard plastic case. This is mine separated from the case and connecting wires.
The heater circuit show 37.6 ohm. The sensor is open circuit.

The end connection block is a very hard epoxy potting compound over the soldered connections. The strip looks fine even under a magnifier so presumably the failure is under that uber hard epoxy.

Wiggly line side (connecting wires snipped off)
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Straight line side
6fd432c2defc4c8853f376fe32b2902f.jpg


d4e3e76bcd85e2a64219c635edad81e2.jpg



Sent somehow.
 
Cheers, great to see what i'm paying all that money for :D
 
I have had three replacements, one lasted around 2000 miles the other 1350 miles, BMW will replace them FOC if within 2 years, I had my last one fitted by an independent, he never charged me fitting either and BMW sent the part direct to him, they do also require setting up on the computer thingy.

BMW parts man did say failures tend to be on bikes that are not used, if ridden regularly they are not prone to failure.
I had a new one fitted in July last year did 5,500 miles in the next 4 weeks, it failed in the 5th week, BMW parts man is guessing I think
 
The fuel pump return flow drives a venturi (aka ejector) that sucks fuel from the RHS over to the left. The fuel gauge sitting on the left spends a long time around 1/2 full as the left is kept topped up. The level then falls quickly as the right side is now dry. All features of the tank shape.

The fuel strip is Mylar plastic with printed copper tracks. It all sits inside a hard plastic case. This is mine separated from the case and connecting wires.
The heater circuit show 37.6 ohm. The sensor is open circuit.

The end connection block is a very hard epoxy potting compound over the soldered connections. The strip looks fine even under a magnifier so presumably the failure is under that uber hard epoxy.

Wiggly line side (connecting wires snipped off)
0f0ddf10043f297ffffe89da0847bddb.jpg


Straight line side
6fd432c2defc4c8853f376fe32b2902f.jpg


d4e3e76bcd85e2a64219c635edad81e2.jpg



Sent somehow.

Very similar set up in lots of electronic components. Printers especially. I'd put money on a dry joint, or a break in the ribbon track somewhere.

I spent a few months resoldering that type of cable and connector lol

Repair wise ...

You could give the zap method a go ...

Solder wise, if you could break all the potting off, and assuming, you could get to the connector / mylar you could reflow the solder.

You cant use a soldering iron, as you will melt the Mylar, you need a waveflow oven, or a very hot source of air. (paint stripper gun),

If you needed more solder, its solder paste, not the hard wire stuff.

You'd need to work out, the distance from the gun to the connector so you don't melt everything ;) then heat the component until the solder

re-flows.

If the break is in the track in the Mylar forget it.

Its near on impossible to split the Mylar, and in doing do, you will invariably destroy the copper track.

Mart
 
The strip is fitted inside a plastic case so it can't flex in use.
I suspect it's failed under the epoxy potting compound possibly at the edge but it's the hardest resin I've come across. So even if we knew exactly what's gone wrong the potting isn't coming off to get at it.



Sent somehow.
 
The strip is fitted inside a plastic case so it can't flex in use.
I suspect it's failed under the epoxy potting compound possibly at the edge but it's the hardest resin I've come across. So even if we knew exactly what's gone wrong the potting isn't coming off to get at it.

Sent somehow.

Potting compound, can be very soft as well lol

if you have the time, and patience, you can file / grind the potting away until you get back to the connector,

What you will have is a 2, 3 or 4 part laminated strip of Mylar, one side contains the copper strip for one side of the circuit, the other the other strip of copper.

The connector end is cut in such a way that the bare copper track is presented ready for a connector.

The loose laminated strips are pressed in a huge hydraulic press, and subjected to lot of heat, this fuses the sheets of Mylar together.

The connector end is then wiped with a flux to clean it, and a film of solder paste is applied the connector is then

popped on, and the whole caboodle is then heat flowed ... the trouble is, to get it to work you have to put a

voltage through it.

Apply a voltage to a resistive circuit, and you get heat.

Heat then re flows the joint, the solder paste moves and hey presto no / intermittent connection.

The potting is to protect the bare end / joint.

Pennies to produce ;)
 
Mine's and 09. My third is still going but writing this could jinx it!
 
Problem 2008 Fuel gauge.

Guy,s

Sorry to jump in on this thread but I have developed a problem with my gauge also. R1200GSA 2008.

I fitted 2 x LED Conversion kits on the main & high beam. The lights work however on the next ride my fuel gauge counted down from 280 miles to zero and warning triangle all within 10 miles. This has to be more than a coincidence!!

I have contacted BMW but same as everyone else they just wanted 220 GBP to replace. I have also contacted an online BMW mechanic and am waiting for a reply.

I have a couple of questions which I am hoping some one may be able to help me with.

1. Can I put a multi meter on the plug that goes into the tank to test the wiring up to the plug?
2. What plug is it for the strip, 3 or 4 wire plug?
3. What colour wires do I need to test across?
4. Do I read DC Volts, Ohms or Continuity?
5. What should the reading be?

If I get a reading to the plug then presumably it is the strip that requires replacement? Or could the Can-bus system require re-setting in some way due to the addition of the LED Driver kits? Don't know what Zapping is either.

I would like this fixed but do not want to pay the 220 GBP if it is something simple I can do. As I previously stated it is a bit too much of a coincidence for this to happen at exactly the same time I installed the new lights.

Any help would be very much appreciated.

Thanks all,

Al.
 
Firstly it IS a coincidence. There is no connection between the fuel gauge and the headlight.

When you get down to the fuel pump cover you will see two connectors. The one with four (4) contacts is the fuel strip. The other one is the fuel pump.
Note, these 90 degs angled connectors often separate the plug before they separate from the socket. The retaining clip is on the frame (bike centreline) side of the connector, hold it away with a fine bladed screwdriver and the whole connector should pull away with minimal force.

The outside two contacts are the fuel strip heater. It's resistance should be about 35 ohm.
The inner pair of contacts are the sensing resistor which should read around 2K ohm but often goes open circuit.

The resistance sensing track can be repaired with a high voltage pulse from a gas lighter piezo spark. However the cracked conductor is still cracked so the fault may well return. Eventually, zapping it has no effect.
 
Google "BMW R1200 fuel strip fix" and there is no end of stuff on the subject.

The fuel strips should be great but the ones they use really are rubbish. BMW solved the problem with float sensor on the Mk3 but earlier model riders are stuck with the remaining stock of faulty sensors.
 
Has anyone any experience of this device: http://hposkam.nl/en/bmw-r1200gs-a-tanklint-naar-vlotter-conversie/ If it works it looks like a permanent, although probably expensive, fix. I'm curious about how it would be calibrated but other than that it looks like a useful piece of kit.

I ordered one at the start of the week, just waiting for it to turn up.

I am also curious about calibration, I'll wait to see what is included with the instructions, if there is nothing I am going to ask Henk the question.

I haven't looked into whether the later float type has any calibration...I assume not.

If I have no information to the contrary I will run a calibration with the float at the lowest level (which I think is effectively what the dry fuel strip calibration is indicating).

Though it probably won't be any time soon because I do not have an actual float to replace the strip with yet!
 
I ordered one at the start of the week, just waiting for it to turn up.

I am also curious about calibration, I'll wait to see what is included with the instructions, if there is nothing I am going to ask Henk the question.

I haven't looked into whether the later float type has any calibration...I assume not.

If I have no information to the contrary I will run a calibration with the float at the lowest level (which I think is effectively what the dry fuel strip calibration is indicating).

Though it probably won't be any time soon because I do not have an actual float to replace the strip with yet!

I have also looked into this option. I sent an email earlier today asking a few questions but not one on calibration. The kit looks quite self explanatory on fitment but if it does require calibration I'm afraid I will be back on here as I don't have a f..king clue...

From memory it's around 78 Eur?? plus postage so beats 220 GBP for a replacement fuel strip fitted from dealers over here. I am still in the process of trying a temp fix via the Zapping route. I am sourcing n piezo igniter off of ebay but the idea of producing a spark next to the fuel tank and into a circuit within the fuel tank goes against common sense. I will aim to minimise any untoward occurrences to myself...

I'll get the missus to do it ...
 
The zapper solution is effective short-term, but mine keeps failing and I hate riding with the warning light flashing and simply want stuff to work as it should (I have relied on resetting the trip my whole life which will not change any time soon).

Having thought about the calibration thing with my brain engaged I do not think the float switch rig up will need calibrating, it is a basic angular movement measurement so should not really need it.

I assume the strip needs calibrating because of manufacturing differences in the resistance of the two circuits in the strip.

The bigger issue I can foresee is which float switch to use...depending on year of bike there is a difference.

Post 2008 R1200GS (not Adventure) it appears straight forward and is the part number listed on Henk's website, which mounts on a tube from the filler neck i.e. it is not bolted onto the fuel pump as per his images.

But for earlier bikes (like mine which is a 2007) the fuel tank is a slightly different shape and the early pre-strip bikes have the float as per his images for the GSA. The BMW parts catalogue only shows the earlier float as a complete fuel pump assembly (though I have not checked Hank's part number for the GSA to see what comes up).

Looking at images the actual float construction and connections appear very similar if not the same for both, but given that one is mounted towards the top of the tank and one half way down I can't help thinking that the version will be relevant to accuracy of the gauge (and if I am going to this effort I'd like it to be accurate afterwards!).

I have both float versions on the way just in case, I guess I'll probably look at this properly next weekend when all the bits are here.
 
Alex,

I have not received a reply yet from Henk but have stated my exact model & year so will leave it up to him to get back to me with the correct specification kit.

"I have both float versions on the way just in case, I guess I'll probably look at this properly next weekend when all the bits are here."

I understand from your post that you have a slightly earlier model than mine and also a GS? If you do find you have a spare kit suitable for a 2008 GSA I would be willing to take it off your hands if it is available.

Keep posting your experiences especially when it comes to the fitment as I would assume there will be quite a few interested parties
 


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