No power to instruments or starting

Got any questions about the BMW's R1200RT/R1250RT's onboard audio, Bluetooth or the Electrical system?
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robparky
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No power to instruments or starting

Post by robparky »

Kept Battery topped up over winter and started ok a few weeks ago. Tried recently and nothing when turn key on instruments, lights, starter switch or my volt meter wired into the aux power circuit.  Any ideas before i start with circuit light- Side stand switch has been playing up along with gear position selector which i believe is damp related.  Battery fully charged.


Thanks Rob



2007 RTP


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David.
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Re: No power to instruments or starting

Post by David. »

Is the "battery fully charged" an indication from a battery charger or has a voltage check on the battery itself been done with a voltmeter.
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robparky
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Re: No power to instruments or starting

Post by robparky »

Battery charger. Multimeter has also given up the ghost.
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David.
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Re: No power to instruments or starting

Post by David. »

The battery may have become sulfated, http://support.rollsbattery.com/en/supp ... -sulfation

"When hard sulfate is present, the battery shows a false voltage, higher than it's true voltage, fooling the voltage regulator into thinking that the battery is fully charged.
This causes the charger to prematurely lower it's current output, leaving the battery discharged."
Last edited by David. on Sun Mar 21, 2021 9:57 am, edited 1 time in total.
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robparky
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Re: No power to instruments or starting

Post by robparky »

Thanks. Will check this out. Neighbour also has old BMWs so enlisting his help.
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robparky
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Re: No power to instruments or starting

Post by robparky »

And the problem was-- loose +ve on the battery- Arghh such basic error. Don't know how it had changed between last start up and now. Hasn't moved off the stand.


Oh well at least it is sorted. Ordering multimeter as treat to self.


Thanks


An embarrassed biker. :alas:
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