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Bike won’t starts , just cranks over , fuel pump doesn’t stop priming

4K views 10 replies 9 participants last post by  dannoxyz 
#1 ·
So I need help , my 03 cbr600rrs fuel pump doesn’t stop priming but bike turns on and when I hit the ignition it doesn’t turn on it just turns over constantly , any help will do , thank you
 
#2 ·
Could it be a leak in the injector? From my understanding, the bike will prime to achieve adequate pressure, so if the injector is leaking, that pressure threshold is never reached, thus prompting the pump to remain pumping.
 
#4 · (Edited)
no, it doesn't do that. fuel pressure isn't indicated to the ECU.

the ECU runs the pump for a couple of seconds on powerup, that's it. no feedback, no prime till it pressures.



if the pump won't stop it could be a stuck relay, a short in the harness, or a failure in the ecm, any number of things...
 
#11 · (Edited)
Swap relays to see if pump relay is stuck on.

Otherwise someone rigged it in desperate attempt to get bike to start. They didn't realise that if ECU won't turn on fuel-pump, it's not gonna fire sparks either. So connecting pump directly to ignition switch doesn't fix a single thing.

Need to restore your wiring back to 100% factory OEM stock condition. Print out this wiring-diagram. Then highlight each and very wire between ignition-switch, to fusebox, to start/stop switch, to engine-stop relay, to fuel-pump relay, to fuel-pump and verify each end of each wire on bike is connected to proper component only.



For example, I did BAS to engine-stop relay for you. Make sure wiring on bike is as connected as shown. Measure resistance to chassis-ground of small red/wht at engine-stop relay. If it's not grounded, engine-stop relay won't turn on power to injectors or coils or ECU. Then ECU won't turn on power to fuel-pump relay to turn on fuel-pump. So forcing pump to run by connecting it directly to ignition-switch won't solve problem of no power to ECU or injectors or coils. Each and every single wire has to be connected exactly like when bike left showroom floor. Otherwise, nothing will work.

 
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