PCX150 fuel pump issue

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eric2cycle
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PCX150 fuel pump issue

Post by eric2cycle »

Good day all...I’m at a loss of direction and hoping for some guidance if possible

PCX150 with 44 miles

Replaced battery back in February and it was starting fine. Was restarted every couple weeks til late March and then it wouldn’t start

Fuel gauge shows full and flashes .....Also the fuel pump doesn’t cycle on key up

I can spray carb cleaner into the inlet and can make it run as long as I keep straying

I checked for power on the two fuel pump wires and the test light is lit on both black and the brown. I do hear a humming coming from behind the airbox briefly upon keying up

Is there a way to throw pos and ground to this fuel pump and have it run continuously or is this pump designed to be pulsed through the ecm and not able to run on by its self

Trying to determine if the ecm is faulty or if the pump is bad or if there’s a relay that I’m missing to check.

Thanks in advance

This is the diagram I’m currently using
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you you
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Re: PCX150 fuel pump issue

Post by you you »

Is that 44,000 miles?

First thing I’d check is fuses..
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Mel46
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Re: PCX150 fuel pump issue

Post by Mel46 »

44 miles??? A 2013 model? Did you miss some zeros?

The fuel gauge shows full but flashes? When was the last time you emptied the gas tank? Fuel DOES go bad.

Like You You said, check your fuses first, but do make sure you have new gas in the tank (if you don't know the age of that fuel, get rid of it, and then add new fuel.) Top off your battery, and then try it again. Batteries, by their nature, discharge just sitting on a shelf or in a bike that is not being used.
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gn2
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Re: PCX150 fuel pump issue

Post by gn2 »

"Replaced battery back in February and it was starting fine. Was restarted every couple weeks til late March and then it wouldn’t start"

Chances are you've killed the battery.
It won't charge back up unless you ride the scooter.
Take the battery out the scooter, get it fully charged on a charger and try again.
ECU possibly has undervoltage protection, i.e. unless the battery is good enough "computer says no".
If the pump doesn't prime, try a fully charged brand new battery.
Definitely dump the fuel and get fresh from a busy fuel station as well.
Four decades on two wheels has taught me nothing, all advice given is guaranteed to be wrong
eric2cycle
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Re: PCX150 fuel pump issue

Post by eric2cycle »

Thanks for the replies

I added 3/4 gallon of fuel and it overflowed the tack filler neck. So it’s full. The gauge flashes as I was thinking it was some kinda code like ecm issues.

Fuel pump won’t run to prime with initial key on. Wire diagram shows brown wire going directly to ecm and the black the power on the ignition switch. Key on it has power to the black wire and also to the brown so I know the pump circuit isn’t fried. But during cranking the brown wire loses power and I was hoping to see pulsing but I don’t see that. Still guessing ecm

It does run with spray fuel through the intake so the rest of the system is functioning

Anyone trouble shot their pump before and determined that their ecm was toast ??
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Re: PCX150 fuel pump issue

Post by easyrider »

If the ECM was bad wouldn't it have a check engine light. Can you jump the wires with a 12 volt good battery going to the pump and see if the pump turns on?
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Re: PCX150 fuel pump issue

Post by you you »

eric2cycle wrote:Thanks for the replies

I added 3/4 gallon of fuel and it overflowed the tack filler neck. So it’s full. The gauge flashes as I was thinking it was some kinda code like ecm issues.

Fuel pump won’t run to prime with initial key on. Wire diagram shows brown wire going directly to ecm and the black the power on the ignition switch. Key on it has power to the black wire and also to the brown so I know the pump circuit isn’t fried. But during cranking the brown wire loses power and I was hoping to see pulsing but I don’t see that. Still guessing ecm

It does run with spray fuel through the intake so the rest of the system is functioning

Anyone trouble shot their pump before and determined that their ecm was toast ??
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Re: PCX150 fuel pump issue

Post by Inoplanetyanin »

Unlikely fuel pump or ecm to be malfunctioning with 44 miles on the odometer.
The question of age of the fuel is extremely relevant given the description.
Starting the bike without riding is a sure way to discharge the battery.

To diagnose fuel pump, I would follow the repair manual procedures, it's hard to guess by looking at diagram and very few if anyone would be able to tell you the diagnostic procedures by memory or knowledge alone.

How does the engine turn when you spin it? What's the battery voltages at rest and during the cranking?

Do you have everything apart to have access to the throttle body or are you spraying the starting fluid through the filter air box?

Please clarify the mileage and the history of the bike, and the state of the battery.
Mikes150pcx
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Re: PCX150 fuel pump issue

Post by Mikes150pcx »

Try tapping the fuel tank when you are turning on or starting, sometimes pumps hang up on a weak spot on the commutator!
Spoolin
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Re: PCX150 fuel pump issue

Post by Spoolin »

Just picked up. A 2013 with 3 miles on it. Yes. Three. 2.8 on the trip odometer. Does the same thing. Full fuel bars and flashing. Continuously. No spaces or anything to portray some sort of engine code.
BRAND NEW, topped off battery. And even with a noco gb55x connected and doesn’t start. Just spins over.
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Re: PCX150 fuel pump issue

Post by hop »

Does the PCX 150 have a fuel tilt switch, that cuts off fuel, when the scooter falls over? Seems that I vaguely recall this on the Forza as a fire safety device. If the scooter was ever layed over, that switch may have activated. Don’t know what it takes to re-set.
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