BMW R1200 R1200GS Fuel Pump Controller Bypass
See also: Failed fuel pump controllers
Updated 14Jan2010 (+ additional comments Oct2011) – see below
How to make your own R1200 / R1200GS Fuel Pump Controller Bypass Power Lead
NOTE: The bypass lead is not intended / designed to replace a working FPC or as a permanent replacement for the FPC, the FPC is there for a purpose (to regulate the voltage supply to the fuel pump and so the speed it runs at and rate of fuel supply). The pypass lead is a something you carry in case of need that will get you home, to your destination in the event of a fuel pump controller failure or keep your bike running until you can source a new Fuel Pump Controller.
Larger versions of the images below can be found here if needed.
Despite BMW having replaced the original Fuel Pump Controller / Regulator (FPC) with a revised version failures are still common even on the latest BMW R1200 / R1200GS motorcycles (2008 onwards). Carrying some form of fuel pump controller bypass power lead might not be a bad idea and will at least get you home / to your destination.
Some riders on tour even take a spare Fuel Pump Controller unit (FPC) with them. Make sure you have a T20 Torx tool in your tool kit so that you can remove the FPC!
There’s information on fuel pump controller failures, some details of ways to bypass a failed fuel pump controller, bypass leads etc on the page linked to at the top of this page but here’s a really neat solution.
Here’s the blow by blow instructions on how to dismantle a failed fuel pump controller to remove the two electrical connectors and make your own bypass lead:
First thing, you’ll need to get your hands on a failed FPC, pop into the workshop of your local BMW Motorcycle Dealer and ask for them to retrieve one from the bin for you….they’re bound to have some!
The circuit board / electronics are sealed in the controllers aluminium casing / heat sink with a soft silicone type sealant – run a sharp blade around the edge between the sealant and the aluminium casing
You will now be able to lift an edge of the sealant and peal it all off….
…to reaveal the contollers innards.
Below, bottom right of the controller’s circuit board, you can see where the three pins from the black electrical connector socket are soldered to the circuit board…
At this point a tool such as a Dremel multitool comes in very handy – using a cutting disk cut through the circuit board as shown below and then use a small screwdriver placed through the hole towards the bottom left of the circuit board to lever / prise it away from the aluminium casing (it’s just held in place now by more silicone type sealant the other side of the board).
If you have access to a ‘desoldering tool’ (?) you can bypass this stage and just desolder and release the connector pins.
Notice how the circuit board components are sealed in the silicone type sealant……could explain why ‘overheating’ of the FPC is one cause of failure, I imagine that sealant to be a good heat insulator and there is no contact between the components and the suposed heat sink!
Just out of curiosity I stripped the silicone type sealant from the FPC circuit board components.
Right, back to the job in hand – cut the blue and yellow wires of the blue connector from the circuit board, as close to the board as you can. Using a small screw driver you lever / prise the black FPC connector from the aluminium casing……photo below shows the process started.
…and out it comes.
Back to the Dremel…. carfully cut through the piece of circuit board, still fixed to the bottom of the connector, around each soldered connector pin. Best done a lttle at a time checking the cut depth in the circuit board regularly as you don’t want to cut into the black plastic connector itself. Trim off the unrequired base from the connector.
You now have the components of your soon to be FPC bypass lead 🙂
Solder the yellow wire from the blue FPC connector plug to pin3 of the black connector and the blue wire to pin2
You can ignore pin1 that connects to the red/blue wire of the bikes wiring loom – that wire normally carries the signal from the bikes ECU that tells the pump modulator at what capacity the fuel pump needs to be operated.
Since you are bypassing the FPC modulator the cable is not used anymore and therefore the pump alway operates at full capacity as it was on previous GS models.
What is the fuel pump controller?
Yes I know my soldering’s not that neat!
Check you have good solder joints / connections and no ‘short’ between the pins with a Multimeter (or bulb and battery flylead tester). Use self amalgamating tape or insulating tape to insulate / isolate the pins/solder joints.
……and finish the job off with some heat shrink tubing (doesn’t have to be yellow:-)
Job done…..and the bike runs with the FPC bypass lead in place.
Lay the wires down flat so they follow the same root as the other wiring and fuel pipe so that the black plastic vented cover can be replaced.
NB: In the case of wet weather there’s a risk of water pooling in the recess that the FPC usually sits over with the potential then for the fuel pump power supply to be shorted. Tape over the vents in the plastic cover with Duct tape (Duck tape) or similar to avoid water ingress – it’s also a good idea to apply Petroleum Jelly or Silicone Grease to the metal contacts of the blue connector.
ukGSer ‘Aggy’ 29Jun2009 “Could you leave the plug in the alloy housing and connect the lead to the bottom so that you could fit the now empty housing on the the original mounts and use the original gasket so that you have a certain amount of waterproofing if you have to use this over a period of time?“
AndyW “I did think of that but….but but…………ok I didn’t! Great idea I see no reason why not other than the small disadvantage of size.
Maybe someone can post me a photo of a version like this sometime please“
Comment Oct2011 by Paul Ewing – What a great article! I have been riding my buddy’s 2007 R1200RT while he is in Iraq. The controller crapped out on me one morning. I replaced it but kept the old one. The one thing I did different [re ‘deluxe bypass below], was, while utilizing the housing, I filled it back up with blue silicon RTV. This way I didn’t need electrical tape or shrink tubing. In addition, I believe the RTV will aid in holding the black plug in the old housing. Either way, my buddy will not be stranded if the new controller craps out. WEll, that is IF he has it with him! Thanks again for the article/fix !
NB: Re RTV Sealant – make sure you use a non conductive type e.g. RTV Silicone Gasket Maker or Liquid Electrical Tape
Update 14Jan2010 – further to my comment above many thanks to New Zealand GS’er Kevan O’Brien for photos of the ‘deluxe’ model of the BMW R Series fuel pump controller bypass:
The dealer that supplied me with the faulty fuel control unit intially cut the plug off thinking I only required the plug hence the black wire extensions – the shrink sleeve was a little big but the right colours
Usual warnings and disclaimers apply!