Battery draining when bike not in use

Ok, so I know there are lots of topics on this, and I've searched as best I can, but my problem seems a little more extreme.

When the bike (8v, 2010) is parked up, the battery drains very rapidly, down from ~13V to 3-4V in less than a week. When I detach the battery from the bike it holds its charge.

I've attached a multimeter, and there appears to be a drain of ~0.5 Amps. When I remove fuse E ("Permanent Positive, ECU Power Supply") the drain drops to zero.

The battery is relatively new (1-2 years) and was carefully prepped for installation. The bike has, until recently, been permanently attached to a trickle-charger when not in use, so this may be a long-standing issue or more recent.

Any ideas what might be causing this? Do I just reattach the trickle-charger and stop worrying?

Oh, and I did the "attach battery, turn ignition key on, wait for startup checks to complete, turn ignition key off, take key out, wait for a few minutes". Drain remained at ~0.5 Amps.

The dash drains around 1.9mA on mine, and some have reported as much as 160mA. 0.5 A is way too high. How's your speedo sensor? I've heard they can inexplicably add to the drain. Try disconnecting it and see if there's a change.

Thanks Beetle. I disconnected the speedo sensor and the current remained constant at 0.51 A, then reconnected it with no change.

I've attached a photo of the multimeter, just in case I'm misreading it... it's connected between the positive terminal of the battery and the positive lead to the battery.

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If the meter is accurate, then it's time to get jiggy with it. If it drops to zero with fuse E out, then either something connected to the ECU is causing it, or there's possibly crud in the ECU connection, or a short somewhere. Pull the ECU out and check the pins are clean and dry.

The ECU connections look to be sparkly clean and dry.

Reconnecting the battery after detaching the ECU, the bike went through a power-on cycle, including a dash speedo sweep, then settled to silence, and the current drain dropped to zero. With the ECU reattached, the current drain was back to 0.5A.

Does that mean that it's something connected to the ECU that's draining the current? Any idea where to look first, and what to look for?

Try disconnecting the dash. In my case I had exactly the same thing happen and it turned out to be the dash. After buying a new one (€€€) the problem was fixed. Of course your problem may lie in a different part.

Just out of curiosity, are you leaving the key truly in the first Off position, or turning it past the lock setting to the Park setting, which leaves a light on for parking purposes? If so, that's your drain.

Good thinking! It never occurred to me that might be happening.

tamu, If you’re not doing that, still might be an issue with the ignition switch.

PJPR01 wrote:

Just out of curiosity, are you leaving the key truly in the first Off position, or turning it past the lock setting to the Park setting, which leaves a light on for parking purposes?  If so, that's your drain.

I'd be delighted if I could trace this to a simple mistake, and I'm still optimistic that I will. Unfortunately it's not this one though!

As well as checking the ignition I'd checked all the lights.

Even .5 amp draw would make some heat. Have you tried using a thermal heat gun to look for warm spots?

Whereabouts in Scotland are you I have a cheapo thermal camera

Ok, so not an ignition switch position issue...I wonder if this is another odd ECU failure.

Have you done any other tinkering recently? Tank off, any wires disconnected recently...anything at all?

it does seem like having it hooked up on the Trickle Charger all this time may have been "masking" the drain for a long time...

Thanks all for your suggestions. We're gradually narrowing this down.

Beetle, I unplugged the dash, and the drain settles to 0.5A again, so I think that's ruled out. Great relief after motor-timothy mentioned the £££ to replace.

PJPR01, it's definitely not the parking light, as I tested that - it draws another ~0.4A when it's on.

Rick, I like the idea of pointing a thermal heat gun at the bike... is that the same as my cheap infra-red thermometer gun?

Tinker, thanks for the offer, I'll keep trying a few other things but I might come back to you... I'm on the West coast, G84.

Thinking about recent fettling I've done (good suggestion PJPR01), I had a dodgy speedo sensor for a long time, and never really understood what I did to fix it earlier this year. But disconnecting it doesn't change the drain. I'd unplugged the ECU to look at the connections then too.

I also attached a replacement Optimate charging adaptor to the battery, and a new USB charger for a camping trip. I've removed both now and the problem remains. I did rummage around a fair bit with the cables there so I'll take a good look for damage.

I also had a dodgy connection in the rear left indicator and fixed it.

The bike had been little-used for a couple of years and I had some real problems with fuelling on the camping trip. Occasional loss of power, spluttering, surging. Finally worked out that violently rocking the bike from side-to-side fixed it in the short term, and in the longer term it just worked itself out. So not likely electrical.

A year ago I had the cams rollerised, but that doesn't seem too relevant.

The bike also has the Guzzitech PCV+AT, airbox lid, and high-flow filter. The PCV power isn't on (no lights) when the battery is draining.

In the last year I fitted the MPH kit to fix the startus interruptus. All connections are clean but I do, every so often, get a click and no start. But after a brief pause (and another click) it always starts at the next attempt.

Finally (hadn't realised how much fettling I'd been doing), I managed to strip the gearbox oil drain plug bolt, so a local friendly motorbike mechanic fixed it for me, between restoring Laverdas.

Any suggestions on what to check next?

Flipping heck you have been busy. The rocking thing from side to side is interesting

tamu wrote:

Thanks all for your suggestions.  We're gradually narrowing this down.

In the last year I fitted the MPH kit to fix the startus interruptus. All connections are clean but I do, every so often, get a click and no start. But after a brief pause (and another click) it always starts at the next attempt.

Any suggestions on what to check next?

That's interesting, since the Startus Interruptus fix should "fix" it without question. Can you double check the relay that you have it all plugged into (making sure to remove those battery terminals first) - Use of a wiring colour guide is a must

I suggest it only because I bought a Norge off a guy who had a similar battery drain issue. When I looked through the wiring I can see they'd done the more "usual" startus interruptus fix - literally pulling the wire out of the socket, and wiring that socket directly to the positive terminal.

Nothing wrong with that, only he'd done it on the wrong bloody relay and it was pulling current all the time!
So not only was the Startus interruptus still happening, but there was also a battery drain issue.

Can't guarantee that's your exact issue but the similarities set off a bell in my head

Given that it only occurs when the ECU is connected, then it has to be something that is powered via the ECU. That is also a concern, as that would potentially mean an issue with the ECU itself.

Next step would be to start disconnecting everything connected to the ECU. If there’s a PCV +AT connected, then we can rule out the O2 sensor, unless for some odd reason it’s still connected and tied up somewhere?

As a first step, disconnect all the relays, including the one hidden under the rear cowling near the tail light.

See if your drain is affected.

tamu wrote:

Thanks all for your suggestions.  We're gradually narrowing this down.

Beetle, I unplugged the dash, and the drain settles to 0.5A again, so I think that's ruled out. Great relief after motor-timothy mentioned the £££ to replace.

PJPR01, it's definitely not the parking light, as I tested that - it draws another ~0.4A when it's on.

Rick, I like the idea of pointing a thermal heat gun at the bike... is that the same as my cheap infra-red thermometer gun?

Tinker, thanks for the offer, I'll keep trying a few other things but I might come back to you... I'm on the West coast, G84.

Thinking about recent fettling I've done (good suggestion PJPR01), I had a dodgy speedo sensor for a long time, and never really understood what I did to fix it earlier this year. But disconnecting it doesn't change the drain. I'd unplugged the ECU to look at the connections then too.

I also attached a replacement Optimate charging adaptor to the battery, and a new USB charger for a camping trip. I've removed both now and the problem remains. I did rummage around a fair bit with the cables there so I'll take a good look for damage.

I also had a dodgy connection in the rear left indicator and fixed it.

The bike had been little-used for a couple of years and I had some real problems with fuelling on the camping trip. Occasional loss of power, spluttering, surging.  Finally worked out that violently rocking the bike from side-to-side fixed it in the short term, and in the longer term it just worked itself out. So not likely electrical.

A year ago I had the cams rollerised, but that doesn't seem too relevant.

The bike also has the Guzzitech PCV+AT, airbox lid, and high-flow filter. The PCV power isn't on (no lights) when the battery is draining.

In the last year I fitted the MPH kit to fix the startus interruptus. All connections are clean but I do, every so often, get a click and no start. But after a brief pause (and another click) it always starts at the next attempt.

Finally (hadn't realised how much fettling I'd been doing), I managed to strip the gearbox oil drain plug bolt, so a local friendly motorbike mechanic fixed it for me, between restoring Laverdas.

Any suggestions on what to check next?

Wow...that's quite a few items to chase down. Hard to guess at this point...
1. A chafed wire somewhere making contact underneath the seat?
2. Incorrect bulb replacement done anywhere (rear indicator mentioned)
3. Maybe a fuse or relay is making contact...worthwhile pulling out all of the fuses, cleaning them or replacing them.
4. Horn positive wire chafed or touching ground somewhere?

This is like a good mystery scavenger hunt!

First thing I'd be doing is pulling off the PC and binning it. Not just because it's a shite device but it's something hacked into the loom and 99% of all problems like this are down to hacked looms.

Have a 2011 Norge which developed a when parked battery discharge issue with no modifications to the wiring, so took all the normal actions replacing alternator & diodes + new battery, looking for obvious shorts/wearing through of wires' insulation; yet nothing resolved this problem.
So installed a battery isolation swith on the negative to ground wire from the battery, every time it's parked for more than a couple of minutes, lift the seat & isolate.
This solves the immediate problem but does resolve the problem itself.

Any ideas, experience & success by others with resolving the when parked discharge on a Norge ?

Will try the IR thermometer scan to see if I can find which wires are flowing the drain current. From the posts on Grisos it sounds like the two more probable culprits are ECM or the dash both of which have lots of diodes.

A delayed update, but the problem is now solved. Thank you all for your help, it was much appreciated.

The original symptoms of the battery drain continued. Eventually a more fatal error of the ECU reporting as being disconnected.

The root cause was a heavily corroded injector relay - the one in the seat cowl. Replacing the relay and the corroded connectors fixed both symptoms.

Thanks again!

Thank you very much for posting the solution

Surprisingly few OP do that but it is so useful the rest of us poor feckers