400ex no power help please
 

I have a 2000 400ex that I just got done putting together. I turned the key on had power but when i hit the start button i heard a click and no power sense. I checked both fuses replaced one. Cleaned my grounds bought a new battery, key switch and starter solenoid and still nothing. I tried jumping the starter solenoid and tried putting Direct power to the starter and still nothing.i did take apart my switch and it was good. (No lights or neutral light. completely dead) Please help so I dont half to send it in and pay out the ass to get it fixed. And please no rude comments. Thanks for the help.

Either the main fuse has gone or you have a bad connection between battery and solenoid or battery and earth. I would check the earth leads on engine and frame first.

400ex no power
 

I checked the 15amp fuse on the starter relay that was good. I replaced the little black 36 dollar main fuse that ties into the rear of the wiring harness. And I sanded ground areas to bare metal and still completely dead.

Check the new battery has some life in it. I have known them to need charging before use. I would get a 12v test lamp, the higher wattage bulb the better, one lead on battery positive, the other to both frame then engine to ensure those are both earthed. Then change to one lead on battery neg, the other onto solenoid pos pole, If you are getting power at all these places, you should get the starter turning when you short across the solenoid, unless the starter is faulty. As for none of the other electrics working, checking the positive side to the ignition switch, and then from the switch to ignition fuse then start button, lights etc should show where that circuit is faulty.

400ex no power
 

Ok I will check that soon and get back to you on it.

400ex no power
 

So I've check everything even replaced the wiring harness, starter switch and starter and still nothing. I even put direct power to the starter and starter solenoid and still nothing. The only thing I can think of is does the engine need to be grounded to the frame? I have one ground that goes from the battery to the sub frame. And my taillight is the only thing that works. So does there need to be more grounds? I did paint it over the winter. And I did run before i tore it apart to redo it so ik the engine is good.

Sorry it takes awhile to reply back I'm not at my shop every day.

"does the engine need to be grounded to the frame?"

Yes, or engine direct to battery, as I wrote before,

"get a 12v test lamp, the higher wattage bulb the better, one lead on battery positive, the other to both frame then engine to ensure those are both earthed."