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Discussion Starter #1
Hey guys it’s been awhile. I recently inquired another KFX. It’s a 2011 has the typical no power to fuel pump and no spark. Neutral light is the only light that comes on. I check and the FI light has no voltage to it when key is on as well. I and getting 12.8 volts at the battery and check the rollover sensor I am getting 0 voltage. The other thing is I can’t get it to read any codes at all. The quad cranks over just fine. Any thoughts? I been searching through this forum for the past week and can’t find what I want. I feel like it’s and ECU but want to get some thoughts. Thanks in advance
 

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Hey guys it’s been awhile. I recently inquired another KFX. It’s a 2011 has the typical no power to fuel pump and no spark. Neutral light is the only light that comes on. I check and the FI light has no voltage to it when key is on as well. I and getting 12.8 volts at the battery and check the rollover sensor I am getting 0 voltage. The other thing is I can’t get it to read any codes at all. The quad cranks over just fine. Any thoughts? I been searching through this forum for the past week and can’t find what I want. I feel like it’s and ECU but want to get some thoughts. Thanks in advance
Do you have 12v voltage on the ignition coil's Y/R wire to frame ground...?

Do you have 4.75~5.25 DCv input voltage on the blue TPS wire...?

Here's the color coded schematic check the ECU Black /Yellow grounds...!!!

see pics
 

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Discussion Starter #4
I did have 12v at the coil. I also checked the ECU pins 21 & 25 had continuity to ground. I’m guessing the guy prior to me jump started it because he put a brand new battery in it that does have 12.8 volts.
 

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I did have 12v at the coil. I also checked the ECU pins 21 & 25 had continuity to ground. I’m guessing the guy prior to me jump started it because he put a brand new battery in it that does have 12.8 volts.
Jumping the battery can burn up your ECU...!!!

Test for 4.75~5.25 DCV input voltage at the TPS blue + & BR -...see pic...

If no reference voltage then your ECU is bad...!!!
 

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try to see if the inturruptor that turns off the motorcycle at the handle is not broken inside what happened to me and the motorcycle wouldn't start
 

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Discussion Starter #8
Getting .4 volts at TPS and nothing changes with key on or off.
 

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Getting .4 volts at TPS and nothing changes with key on or off.
Your quote from an above post...(I’m guessing the guy prior to me jump started it)

The white wire is constant power to the ECU whether the Key is ON or OFF, memory for the self diagnostic circuit ....thus the culprit for the battery drain that many have suffered...See pic marked in red...

I suspect your ECU is bad... check the voltage regulator for being the bad too...see pic

Jumping the kfx battery rated at 70cca with a 400 cca car battery can fry the voltage regulator, ECU or both...
 

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Discussion Starter #10
D&C and A&F are out of spec testing the rectifier/rectifier so I’m goi to replace it first.
 

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D&C and A&F are out of spec testing the rectifier/rectifier so I’m goi to replace it first.
Quick question...Does your KFX have a N/O normally open tethered kill switch connecting to the crank sensor...??

Also check your crank sensor/pulse coil for continuity & peak voltage...

Peak voltage can be done only with an analog multimeter with a needle set it to 10 ACV or lower voltage & watch the needle bounce at or above 2 v... see pics
 

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Discussion Starter #12
It does not have a teather
 

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Discussion Starter #13
I went ahead and got a procom ECU and new rectifier cause mine checked bad. I can get it to backfire but not run. Have good park. Battery at 12.8 volts. Idle screw at 20 clicks out. I tryed 16-28 and nothing. It’s pops sometime but will not fire
 

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Discussion Starter #14

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Just check TPS an it’s right at .6 and [email protected] Any thoughts?
How old is the gas...?..if new/good...

Test the fuel flow rate of the fuel pump..?

Check the valve timing...?

Check the compression...65~75 psi normal...49~85 psi usable...

Check or replace your water temp sensor...see pictures below
 

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Discussion Starter #16
I found the timing was way off. I have oil in the exhaust pipe. I’m guessing maybe a cracked head to oil gallery of valve seals. I had it running it starts find good compression but smoke like a train.
 
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