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Flat battery then no fuel gauge

4K views 17 replies 5 participants last post by  jimmcd1974 
#1 ·
Hello folks, I hope you are all staying safe in these dark times.

For various reasons I've not been using the Commander much for the last couple of months and the last few times I used it the bike was reluctant to start.

This morning I thought I'd better try and start it after not using it for 3 weeks and it would barely turn over let alone start.

It looked like a bit of a job to get the battery out so I disconnected it and charged it on the bike.

A bit of a problem reconnecting as the negative terminal seems to have stripped threads and couldn't get the bolt to stay in place. I found a slightly longer bolt which worked (although I'm not convinced it'll stay connected as there must be the tiniest bit of thread engaged)

Turned the bike over and it started first push!!!

Yay, but hang on, the fuel gauge isn't working.

Tried the old IT support technique of switching it on and off a few times but no luck. Still no fuel gauge.

The battery is 6 years old and as the bike lives outside it's seen some pretty cold winters when it's hardly been used. Being outside meant I can't connect an optimiser and have never charged the battery before.

I think I need a new battery as I'm worried about the connection coming loose anyway.

Any ideas about the fuel gauge folks?

Thanks.

Dick
 
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#3 ·
Thanks. Not yet. I'm hoping that might be the case. I'm not too keen on trying it at the moment as we're in lockdown here and I want to respect that.

I've had issues with it before when it was showing nearly empty and I couldn't see how it could be as I'd filled up a few days before. Sure enough when I tried to put some fuel in I only managed 5 litres! It's been fine since then.
 
#5 ·
Thanks. I know it can take a time to do that but there was at least half a tank there. Also when I switched it on the gauge would swing up to full then back down again and then settle at the right level. It's not doing that now. I'll see what happens when I eventually take it out.
 
#9 ·
I did wonder about that and maybe a ride will free it. Despite my misgivings about breaking the "no non-essential travel" restrictions I need to fill up as I've just found out I may be called away unexpectedly so perhaps I'll have an answer in the next few days. Thanks
 
#10 ·
Hi Dickenbacker:
Looks like "old tech" - just a floating bobbin!!
May be stuck - perhaps you can see it if tank is near empty and wiggle with screwdriver.
Best
Chris
 
#13 ·
Well, I took the bike out today and topped up with fuel. In the end it only needed 7 litres.

Riding to the petrol station the gauge stayed glued to the empty position. After filling up though it gradually climbed back to full although it took several miles.

So, no idea what happened to the gauge but at least it's working. Perhaps the sensor is on the blink but as I'm likely to not be using it for a while it could be some time before I find out!

Thanks for everyone's input.

Cheers

Dick
 
#15 ·
Excellent - glad you got it sorted. As I don’t believe in coincidences, I’m looking for a cause related to the disconnection of the battery. As others have pointed out, there’s nothing high tech about the sensor - in the olden days that sensor would have been wired straight to the gauge and it would have moved the needle based on voltage more or less instantly, apart from some damping. Nowadays I would think it’s connected to the ECU, and the ECU is connected to the needle. Is it possible that the ECU fuel setting was zero’d by the disconnection, and it was just taking its time getting the reading right. Don’t think it sample the signal all that often, as shown by the time it takes to register correctly after every fill-up. Thoughts, anyone?
 
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