Pump hums when switched on but does not work more than 20 seconds

start /run capacitor failed ( motor just hums)
overloaded -- thermal switch off or faulty motor does nothing
pump seized -- motor does nothing and trips the thermal switch with in seconds of being switched on

Ford is the only one I know of that uses a cutoff switch. GM use a relay usually in the under hood fuse box. Try opening gas cap & have someone put their ear to it, turn key on without starting, they should hear fuel pump hum for a few seconds, meaning it's working. If not check for blown fuse or bad relay, if you find something wrong with fuse or relay, replace it, & do the test again, if still no hum at the pump, it's likely pump is bad or you have a bad connection or bad ground.

Assuming you've successfully started the bike in the past.
I'm going to say that maybe it is a cut out feature issue. Check your sides switch is working. Check your clutch switch is working.
Check your kill switch is working. Also check your neutral switch is working.
Check your main fuse at your battery is not broken.

If the caps and switch, etc.. are checked most likely your motor is toasted. You will need to replace it. Good Luck...

the start switch is dirty, needs to be cleaned, or the start capacitor is week or bad . carfully clean the switch first, use the sandpaper off a match book to clean the points

you've got dual tanks? the selector switch may be bad,on the dash., check those 1st. remove the panel that switches the tank to tank,make sure that the connections good. switch to main tank and make sure that fuels in the main tank.if you have fuel in main tank,thats good. but keep in mind that you also have an electric fuel pump,located just under the driverside door frame.when you turn your key to 'on' position,do you hear that electric fuel pump humming for 10 to 15 seconds? been there and done that before. because you have 2 tanks it takes alot of fuel pressure to power your engine. when you turn your keyswitch 'on' do you hear the fuel pump humming? if not,then you can check the main fuse box under the hood. look for a square black box,usually on driverside fenderwell under the hood. lift cover off and check for blown fuses or bad relays. under the fuse cover you should see locations of relays and fuse locations. the #1problem{fuel related} with your year truck is a bad electric fuel pump. take my advice and replace the pump with the replacement pump recommended by advance auto,or nappa auto parts. or else dealer parts. autozone parts come from mexico[mostly] i hate to promote anyone autoparts,but learn by my own hard work replacing bad parts and by whats warranty and whats not.thank you for choosing fixya.com and feel free to choose your own parts store! i do however,promote fixya.com!!!!

turn off power open access panel and check pump close water valves to pump and disconnect lines ckeck pump for debris that may be stuck in pump blocking impeller if clear than lube motor bearings and try moving impeller back and forth to free motor once free return and test pump

group head is blocked. remove centre screw from the group head remove spring and valve, clean and re assemble.

the switch is supose to be in the down position. push the switch back down get in car and close all windows and turn key to on position and lisen for the fuel pump to run for a couple seconds sounds like a low hum that only last for 2 to 3 seconds if you dont hear this then the fuel pump is bad

this is a direct drive,no belts,good washer you won't find any washers built like this anymore,on top console pop off the clips on each side,then remove the two phillips screws,lift the top console,with a regular screw driver stick in into the hole where the clip goes into frame and on top of the clip and push forwards and the clip will pop out,then there's a lid switch a white wire connector on the right top,unplug it,now grab the cabinet and tilt it up and pull back and remove the cabinet.if the motor is humming and it's not draining it sounds like some thing is stuck in the pump or a bad pump,look down and you'll see the pump on the front of the motor,with a screw driver pop off the two clips and slide the pump off,get a piece of wire and stick it into the white connector where you disconnected the lid switch from,this will jump out the switch,set the timer to spin and run it,if the motor spins then you know the pump is jammed or bad.let me know what you find.the pump part is WP3363394