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Hi guys,

I haven't rode my bike for about 2 months due to work constraint. Recently , i tried to start my bike but it failed. Upon turning on, I heard no fuel pump but the starter did crank when I pressed the starter switch.The LCD did light up, Anyone had experience this kind of problem before? Appreciate if I could some help from you guys. Rebel is my very first bike. Hoping I could learn something from this experience.

Things that i tried so far.
1) checked the battery voltage and recharged.
2) wiggle the kill switch cable hoping it would work.
3) Fill up the gas tank.

Thank you.
 

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Fuel pumps are the first thing to go when you let a bike sit too long with old, untreated fuel in it. If you don't hear it cycle and it wasn't accidentally disconnected, it's probably gone bad.
 

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don't hear the fuel pump run briefly but starter cranks and dash lights work?
to rule out fuel pump failure
lift tank
disconnect 3P fuel pump connector
put voltmeter across Y/R (+) wire and B/G (-) wire on wire harness side of connector
with engine stop switch in run position turn key on
should read battery voltage for 2 seconds
if you get voltage for 2 seconds fuel pump is bad
if no voltage you could have a much more involved diagnostic job...get the service manual to proceed with wiring/relay checking
 
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Agreed load test the battery.
Batteries only last 3 to 4 years.
IF you added anything to the bike electrically it could be connected wrong and taking the battery down.
if the starter cranks the engine over the battery would certainly have enough power to run the fuel pump when he turns the key on

guess some more
 
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What harm would it be to load test the battery? Remember K.I.S.S.
his problem is the fuel pump doesn't run...bike isn't gonna start

you did read his battery has enough power to crank the engine?

seems to me you would want to see why the fuel pump doesn't work
 
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The point being made is the battery cranking over the engine IS a simple load test. If it has good compression and spark plugs weren't removed, the battery passes the load test as long as it the starter cranks with authority. It only takes a small fraction of that energy to crank the fuel pump so it ain't the battery.
 

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Eh Ima disagree with battery is good because starter turns, depending on how the ecu is set up and starter is wired it is possible to have a battery that has sufficient amps to turn the starter at a dog race speed, but voltage is not high enough so the ecu doesn't allow things to happen. load test SHOULD include seeing how far VOLTAGE drops when battery is under a load, and a freshly charged battery CAN FAIL this test and not start the bike, there's not often I know I'm right, but about this, I know, maybe it applies to this bike.

if anyone wants details about battery innards etc , i'll provide
 

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Eh Ima disagree with battery is good because starter turns, depending on how the ecu is set up and starter is wired it is possible to have a battery that has sufficient amps to turn the starter at a dog race speed, but voltage is not high enough so the ecu doesn't allow things to happen. load test SHOULD include seeing how far VOLTAGE drops when battery is under a load, and a freshly charged battery CAN FAIL this test and not start the bike, there's not often I know I'm right, but about this, I know, maybe it applies to this bike.

if anyone wants details about battery innards etc , i'll provide
Only problem with that theory is that the ECU and fuel pump gets power before the starter motor has a chance to drain the available energy stored in the battery and it takes very little to get it to cycle. It makes no sense that a battery can't supply a low amp fuel pump with enough power to turn it and yet have enough to crank the starter. I know for a fact that a battery will always cycle the fuel pump if it has enough juice to budge the starter motor.

As for the ECU getting sufficient voltage, it takes well under 12V to get it (and the pump) to work. Under normal conditions, the battery voltage drops to less than 10V as the starter is cranking but the ECU, relay and pump have to stay energized for the bike to start. Before the starter button is pushed, there's more than enough battery power to get the ECU and pump going. I guarantee the starter motor wouldn't crank if the battery was so low that it couldn't even power up the ECU or cycle the pump.
 

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OK, 1 it ain't theory
2 I din't say it applied to your bike
3 it does apply to mine
thanks for your input
 
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