2012 UXV 500 Fuel Pump

[knukey]

I have a no turn on fuel pump.  Anyone cross reference a replacement?

[CROSSBOLT]

Probably a Yamaha is a direct for the pump only. Stig did that with his Like 200i. The Kymco scheme is pump and fuel gage sender as a unit which is really pricey. Pump alone is pretty reasonable.

[knukey]

I just checked the power on the fuel pump. It appears that I'm not getting power to the fuel pump. Does anybody have a link to a wiring diagram?

[CROSSBOLT]

Aha! Check fuses first. The pump is turned on and off by the ECU through a relay. What do you see and hear when you turn the key on?

[knukey]

No fuel pump during key on, all fuses and relay
good.

[CROSSBOLT]

Volt meter test at pump/fuel gage sender: 1. 12 volts, no pump sound, pump bad 2. Zero volts or low volts, pump good, something upstream bad. You can use a test light instead of volt meter.

[knukey]

I had a mechanic friend check the unit.  He found the fuses and all relays good.  I have no spark either.  We were able to get the fuel pump to come on with direct power.  When you turn the key the CEL does not light up to check codes manually.  He's thinking the ECU is bad.  Any input?  Suggestions on where to get a new ECU?  Is the ECU plug and play or will it need to be programmed?
Are there any common ground fault locations I should check?

[CROSSBOLT]

Direct power to fuel pump proves the pump works. You say you have no spark. Does that mean the starter actually cranks the engine over? Is there anything else you can tell us about this increasing collection of issues?

[knukey]

Yes the engine cranks, but checked and I have no fuel pump or spark.  What, other than fuses and relays, could it be other than the ECU?

[CROSSBOLT]

Well, the voltmeter check at the pump connector may start a troubleshooting path to determine if the problem is the ECU or not. Additionally, a voltage check of the connector at the ECU couldvsee if it gets power when the key is turned on.

I checked mine this morning and the pump runs about a long 15 seconds when the key is first turned on. That would be a good ECU check at the pump. Then do the same at the ECU where the pump signal goes to the relay. Toss in a voltage check at the relay for the power to the switch contacts and the signal from the ECU. That kinda stuff.

[knukey]

Crossbolt,

I appreciate all your help!

He checked all of these points and it all points back to the ECU.  I ordered one.

Are ECU failures common?

[CROSSBOLT]

No, ECU work good, last a long time normally. Yours COULD BE the first one! Please post your results after you get the replacement in!

Actually, I forgot to mention your problem could be bad contact in one or more connectors...

[knukey]

Replaced ECU and it runs fine now.

[CROSSBOLT]

Good show! Good to know the sequence of testing to eliminate all the cheap stuff first!