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Shorted battery leads to rough running ?

2K views 7 replies 6 participants last post by  Juice 
#1 ·
Hi All,
first post from a new user - owned a Classic from new since 2014.
I have a lithium battery fitted to my 2014 RNineT. I had a little battery booster cable fitted, but when disconnecting it, I clumsily/accidentally shorted the cable and it welded itself together for a couple of seconds - smokey - until I could separate the cables ! The key was not even in the bike when the short happened. The battery has cut itself off for a while ( no ignition lights or response when they key turned on ) and then provided current again after a few minutes. Originally the fuel pump didn't appear to pump up with the key and the motor wouldn't start. After a few more tries on the starter I can hear the fuel pump come in and the bike starts but super rough - like it's running on one cylinder. I have spark to both plugs, but it runs super rough and is not rideable.
The early bikes didn't have a physical fuse and relied on the CANbus to manage shorts etc.
My GS911 report is reporting a fault on the engine controller - fuel pump 10168 - Fuel pump voltage 9.61v - Fuel Pressure 0.05psi - Engine RPM 240.0.
So has anyone suffered a similar problem post shorted battery ?
Even though the fuel pump is clearly 'spooling up' pressure ( I can hear it as normal when ignition is turned on ), could the injection system be faulty or the fuel pump control/driver module be faulty/damaged by the short. Is there a way to test the fuel pump control/driver module once removed ?
Thanks for any ideas.
 
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#2 ·
With the ignition turned off, have you tried disconnecting the positive lead to the battery at the battery terminal, leaving it for a couple of minutes and then reconnecting it again? This might reset the bike ECU to some extent. Just a guess.
 
#4 ·
I’ve run it with a new battery and also disconnected the battery for a few days to try to reset the ecu with no effect. Is there a particular way to reset the ecu, ecu voodoo ?
Am recovering from surgery atm, and can’t ride, so I go back the my nineT problem every week or so, otherwise it’s a depressing type of problem. Next step is borrow the ecu off my mates nineT, swap that out and see how I go. Then try the fuel pump controller swap.
 
#6 ·
Update - I have got the issue down to the fact that she is only running on one cylinder - has a spark but no fuel. So I have swapped the tank off my mates nineT onto my bike with no change, so not the fuel pump. I have swapped the coils and plugs with no change. I have disconnected the ecu for days and reconnected with no change, so no reset ecu improvement. I swapped over the ecus between bikes but they appear to be coded to the ignition switches and refuse to turn over.
I’m officially beaten so she’s off to the bmw dealer for some professional help, it was good to try myself though and thx for the suggestions.
 
#7 ·
Check the injector and its wiring to the offending cylinder. Also check the throttle cable on both cylinders, in earlier oilheads the cable gets dislodged from the throttle body and causes a single cylinder like running condition. If all that's good try swapping injectors side to side and see if the problem follows the injector
 
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