Turn key and absolutely nothing happens

kevinheb · Two Stroke Sniffer Joined: 22 Apr 2012 Karma :

I have a BMW F650CS 02. Normally when you turn the key from "off" to "on" the bike makes a whirring noise and the display lights come on for a few seconds. I haven't ridden the bike for a couple of weeks, and last night when I tried to start it, when I got on the bike with the key in "off" position, the time on the display was showing. When I turned the key to the "on" position, absolutely nothing happened. No lights on the dash, the time lcd went blank, and the bike made no whirring.

When I turn the key to the "off" position again, the time reappears, and the speedo vibrates for a few seconds and I can hear a quiet whirring coming from the bike for a few seconds.

I believe that the battery is ok, with a multimeter across the battery the voltage is 12.5V and I have tried charging the battery, but the charger says that the battery is charged. I have also checked the fuses with the multimeter, which says that the fuses have no resistance across the them.

I'm at a real loss to work out what is wrong with the bike, and would appreciate any advice, thanks
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YBR 125 (sold) > YBR 250 (sold as spares/repair) > F650CS

kevinheb · Two Stroke Sniffer Joined: 22 Apr 2012 Karma :

Quoted from Richard M on another forum

"That is the typical symptom of a dead battery. You can not go by the voltage reading. These German-made Exide AGM batteries tend to break internally after a while (mine only lasted 6 months) and the internal connections will fail if any load in placed on them. But they have just enough of a connection within the battery to run a voltmeter. Try hooking the battery up to a light bulb, or install it in your bike and turn the ignition on, then check the voltage. Chances are that the voltage will be zip under a load."

Having measured the voltage across the battery when the ignition is on, it drops to about 0.5V, which I'm guessing, means I'll need to get a new battery
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YBR 125 (sold) > YBR 250 (sold as spares/repair) > F650CS

Pete. · Super Spammer Joined: 22 Aug 2006 Karma :

More likely you turned the key to far and ran it flat with the parking light.
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a.k.a 'Geri'

132.9mph off and walked away. Gear is good, gear is good, gear is very very good Very Happy

bugeye_bob · World Chat Champion Joined: 05 Sep 2013 Karma :

Can you try a set of jump leads to confirm if it is the battery ?

mentalboy · World Chat Champion Joined: 05 May 2012 Karma :

kevinheb · Two Stroke Sniffer Joined: 22 Apr 2012 Karma :

When I plug in a charger when the ignition is off, the charger says that the battery is full, but when I connect the charger with the ignition on, the leds on the charger just blink
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YBR 125 (sold) > YBR 250 (sold as spares/repair) > F650CS

doggone · World Chat Champion Joined: 20 May 2004 Karma :

Jump leads from another vehicle if you can.

MCN · Super Spammer Joined: 22 Jul 2015 Karma :

A new battery will be about £60+.
A Battery conditioner about £40.

You really should have both in your case. If you leave the bike for any length of time a month or two without any action it can ruin a battery quickly.
Conditioners help keep the battery in top nik so they should last longer over all.

I would:
Try to charge the battery and test if it'll start the beast.
If not, buy a new battery.
Then you need to buy a conditioner for maintenance and less butt-hurt.

Keep the top of your battery clean too.
A wee test:
If you have your multimeter handy, connect one lead to a post.
Touch/Drag the other lead around the top of the battery.
Observe the voltage reading. Shocked

Wipe off any shit etc. from the top of the battery and re-test.
Observe the voltage reading.
Laughing

It's not massive amps, volts, ohms etc. but it is a trickle or constant drain 24/7.
Your trickle charger/optimizer will easily accommodate for this 'leakage'.

Taught2BCauti... · World Chat Champion Joined: 12 Jan 2012 Karma :

FWIW, I also think you have a battery problem.

Sometimes when a battery fails, a voltmeter appears to show that everything is fine, but internally, the current capacity isn't up to the job.

Measure the voltage again with the ignition on, and see if you get a lower reading.

This is why the battery charger says "Full", because it can't get any more juice into it.

You need a special piece of equipment called a 'Drop Tester' to measure the battery capacity - a multi-meter won't do it.
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doggone · World Chat Champion Joined: 20 May 2004 Karma :

Or jump start it from another vehicle.

Agree smart charges won't always start to work if it's very low.
It might still be OK for a while once charged again, but they soon go downhill after being totally flat, as irreversible damage is caused.

MattEMulsion · World Chat Champion Joined: 29 Aug 2004 Karma :

Just check that you haven't knocked the kill switch to 'off' whilst you.are there.
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Yamaha YZF-R6

kevinheb · Two Stroke Sniffer Joined: 22 Apr 2012 Karma :

I've been charging it for a few hours now, the dash lights are on, but if I try the indicators or front lights, they go dead again. I'll keep trying for a few more hours, but I suspect I'll need a new battery
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YBR 125 (sold) > YBR 250 (sold as spares/repair) > F650CS

Pete. · Super Spammer Joined: 22 Aug 2006 Karma :

kevinheb · Two Stroke Sniffer Joined: 22 Apr 2012 Karma :

Pete, what do you mean by "the tender"?
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YBR 125 (sold) > YBR 250 (sold as spares/repair) > F650CS

barrkel · World Chat Champion Joined: 30 Jul 2012 Karma :

Pete. · Super Spammer Joined: 22 Aug 2006 Karma :

Snodvan · Spanner Monkey Joined: 22 Jul 2010 Karma :

Kevin

I have exactly the same bike - 02 BMW CS
I had virtually the SAME PROBLEM this last week
Turned out to be the fuse in the Datatool system (10A miniature spade type). Check your fuse. If the fuse has gone the Datatool alarm will shut down the bike totally

If the fuse is ok then - battery
Getting the battery out of the cradle on a Scarver is a pain in the arse BUT I would struggle and then charge the battery on the bench where I can also properly check electrolyte levels and do a "power test" ie wire a headlamp bulb across the battery and note how long it takes for the voltage to drop to (say) 12 or below.

Snod
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04 (UK Reg) BMW F650cs, but really 02 first Reg in Holland

MCN · Super Spammer Joined: 22 Jul 2015 Karma :

kevinheb · Two Stroke Sniffer Joined: 22 Apr 2012 Karma :

Thanks Snodvan, but I don't have an alarm fitted, so its unlikely to be that. I have checked all 4 of the fuses next to the battery and they are all working
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YBR 125 (sold) > YBR 250 (sold as spares/repair) > F650CS

davebike · World Chat Champion Joined: 15 Nov 2013 Karma :

Could be BMW's inigtion switch wire snapping I seen it more on the bigger bikes

turn on inigtion check battery voltage is good (still over 12v)
check voltage at fuse box ( not main fuse )

If no volts there

Look at the wire from the inigtion switch you have to cut and remove the plastic sieve the wires tend to brake near where there are cable tied to the frame and turning the steering flexes them
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Dave
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