Okay, so here's the dilemma in short. I have a 2009 klx250s, just went through it and fixed a valve cover gasket leak, charged up the battery and took it for a little trip around town. Ran fine, popping on deceleration as usual, got home parked it. Went out about 2 hours later, pulled the air box lid, inserted key into ignition, and nothing. No power to the speedo, nothing. I checked battery voltage, good. Checked fuses, good.

So, now I have pulled the battery and hooked it up to the Battery Tender for the time being. Don't know if I'm overlooking anything, but all seems well, never had this happen before, I've had the low battery with it trying to kick, but never had zero speedo or lights. It is the stock battery, do they have a lifespan, even when the voltage is fine. I checked voltage up to the first block where it goes to the first module, it has voltage on the input side, but nothing on the other side after the fuse, fuse is ok.

Hope somebody out there has some idea what the problem is, really want to go riding sooner than later.

 

Bad ground perhaps

 

I think this might be an important clue. Don't assume that just because a fuse LOOKS ok that it is ok. If you have a meter, test it. If not, replace it (they're cheap). You could also have a bad connection inside the fuse block itself, but make sure it's not the fuse first.

 

Thanks, I've checked my connections for continuity, as well as the fuses. All rings out well. I am a bit su****ious about the module that the positive wire goes to right off the battery, the one with the 20 amp fuse. Not sure what that is called, but without a wiring diagram I'm somewhat lost.

 

I've had plugs vibrate loose and leave me baffled, until I started pulling on all the connectors and one came loose. Plugged it back in and voila. It had looked plugged in, but the tab that holds it together had not been inserted far enough, so it vibrated apart.
Maybe it's that simple.

 

Did you stop the engine with the kill button, if so it is still depressed and will cut all electronics.
Put the battery in, with a VOM unit set at voltage, start at battery terminal and start checking the voltage all the way along the wiring path at the connectors. There is a big wiring harness on top of the frame under the seat, maybe one became disconnected when you yanked the air box or got it got snagged on the seat when removed.

 

Alrighty, here's what I discovered during my morning investigation. I began tracing and "ringing out" wires up to the ignition switch, kill switch etc... All were good to go, plugged everything back in minus headlight, voila we have gauges blinkers and starter bumps. Now, plug in headlight and it all goes dead? I'm an electrician, but don't deal with DC battery systems, shall I assume my battery is kaput and needs to be replaced? My only thought is to get the tank back on start it up, plug in the headlight and see what happens.

 

Put a meter on your battery. Turn the ignition on. What does your battery voltage read? I just posted a video in another thread on testing batteries. One battery read 12.25V and with a single turn signal bulb on it the voltage dropped to 0V. May be your issue.

 

Yes try to load test the battery. A stuffed battery can still read 12 volts but when a load is applied, the voltage drops instantly. A headlight is ideal for doing this. As a multimeter is a low impedence instrument, it's current draw is negligible. That's why you'll read 12 volts. Has the bike been sitting around for awhile? Maybe the battery has sulphated...

 

Thanks for all the suggestions gentlemen. Picked up a new battery and all is well. I'll be sure to keep it on the the tender when it sits for awhile.