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Discussion Starter #1
looking for help on getting running again, fuel supply is good, has spark and good compression. it acts like what most describe as roll over sensor issues. voltage in is good but was only showing .62 out, so I bought the bypass kit and installed with same results. come to find out my y/g is back feeding the roll over 3v. but once you plug it in its only .6v Where is the back feed volts coming from? Bad ecu or sensor somewhere?
 

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looking for help on getting running again, fuel supply is good, has spark and good compression. it acts like what most describe as roll over sensor issues. voltage in is good but was only showing .62 out, so I bought the bypass kit and installed with same results. come to find out my y/g is back feeding the roll over 3v. but once you plug it in its only .6v Where is the back feed volts coming from? Bad ecu or sensor somewhere?
Make sure your battery is fully charged 12.8 volts standard before testing voltages...!!

Battery voltage below 11.5 volts quad will not start...!!

The vehicle down sensor Y/G voltage is to be 3.7~4.4 DCV for the motor to start...anything below 3.5 & lower it will not

The ECU's reference voltage is 4.75~5.25 DCV for all sensor's can you test the reference/input voltage of another sensor like the TPS/throttle positioning sensor...??

reference wire is lite blue, ground is black/brown

See picture...
 

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Discussion Starter #3
looking for help on getting running again, fuel supply is good, has spark and good compression. it acts like what most describe as roll over sensor issues. voltage in is good but was only showing .62 out, so I bought the bypass kit and installed with same results. come to find out my y/g is back feeding the roll over 3v. but once you plug it in its only .6v Where is the back feed volts coming from? Bad ecu or sensor somewhere?
Make sure your battery is fully charged 12.8 volts standard before testing voltages...!!

Battery voltage below 11.5 volts quad will not start...!!

The vehicle down sensor Y/G voltage is to be 3.7~4.4 DCV for the motor to start...anything below 3.5 & lower it will not

The ECU's reference voltage is 4.75~5.25 DCV for all sensor's can you test the reference/input voltage of another sensor like the TPS/throttle positioning sensor...??

reference wire is lite blue, ground is black/brown

See picture...
Yes fully charged brand new battery. Tps volts in and out are at manual spec. The roll over has 5.+volts input at incoming wire KMS bypass just installed. The issue I see is that when I unplug the roll over and check volts I have proper 5v going towards sensor but I also have 3v showing up on the yellow/green coming from ecu. When I plug in original roll over or the KMS the volts on the y/g drops to .63v going back to ecu. To me it's seems like ECU is messed up
 

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looking for help on getting running again, fuel supply is good, has spark and good compression. it acts like what most describe as roll over sensor issues. voltage in is good but was only showing .62 out, so I bought the bypass kit and installed with same results. come to find out my y/g is back feeding the roll over 3v. but once you plug it in its only .6v Where is the back feed volts coming from? Bad ecu or sensor somewhere?
Make sure your battery is fully charged 12.8 volts standard before testing voltages...!!

Battery voltage below 11.5 volts quad will not start...!!

The vehicle down sensor Y/G voltage is to be 3.7~4.4 DCV for the motor to start...anything below 3.5 & lower it will not

The ECU's reference voltage is 4.75~5.25 DCV for all sensor's can you test the reference/input voltage of another sensor like the TPS/throttle positioning sensor...??

reference wire is lite blue, ground is black/brown

See picture...
Yes fully charged brand new battery. Tps volts in and out are at manual spec. The roll over has 5.+volts input at incoming wire KMS bypass just installed. The issue I see is that when I unplug the roll over and check volts I have proper 5v going towards sensor but I also have 3v showing up on the yellow/green coming from ecu. When I plug in original roll over or the KMS the volts on the y/g drops to .63v going back to ecu. To me it's seems like ECU is messed up
The test results on the Y/G wire are

unplugged 5v & with either KMS or down sensor installed 0.62v & the Y/G wire is now 3v... correct?

with the vehicle down sensor plugged in!...Did you get the same 0.62v whether you tilted it in the manual testing...???

Is your ECU (OEM stock)..?

It can be a bad ecu, bad connection/moister at the ECU connector into the harness...Try electronic cleaner or rubbing alcohol to clean the ecu pins & connector and see if you have the same test results..Caution don't damage the ECU pins

If so, I'd say it's the ECU..
 

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Discussion Starter #5
Make sure your battery is fully charged 12.8 volts standard before testing voltages...!!

Battery voltage below 11.5 volts quad will not start...!!

The vehicle down sensor Y/G voltage is to be 3.7~4.4 DCV for the motor to start...anything below 3.5 & lower it will not

The ECU's reference voltage is 4.75~5.25 DCV for all sensor's can you test the reference/input voltage of another sensor like the TPS/throttle positioning sensor...??

reference wire is lite blue, ground is black/brown

See picture...
Yes fully charged brand new battery. Tps volts in and out are at manual spec. The roll over has 5.+volts input at incoming wire KMS bypass just installed. The issue I see is that when I unplug the roll over and check volts I have proper 5v going towards sensor but I also have 3v showing up on the yellow/green coming from ecu. When I plug in original roll over or the KMS the volts on the y/g drops to .63v going back to ecu. To me it's seems like ECU is messed up
The test results on the Y/G wire are

unplugged 5v & with either KMS or down sensor installed 0.62v & the Y/G wire is now 3v... correct?

with the vehicle down sensor plugged in!...Did you get the same 0.62v whether you tilted it in the manual testing...???

Is your ECU (OEM stock)..?

It can be a bad ecu, bad connection/moister at the ECU connector into the harness...Try electronic cleaner or rubbing alcohol to clean the ecu pins & connector and see if you have the same test results..Caution don't damage the ECU pins

If so, I'd say it's the ECU..


Yes blue reference wire shows 5.2v with sensor plugged or unplugged. The y/g shows me 3.4v with nothing plugged in and then .62v when either sensor is plugged in. I checked/ blew out pins and no changes. I traced the y/g back to ecu to check for any worn spots and nothing. Ecu is stock as far as I am aware Only thing I noticed in my checking that didn't jog with the manual was in reference to ecu power source inspection page 3-65. Is there listing correct? Mine is opposite of what I calls for. I have battery v at terminal 13 key off and none at 29. Both have v with key on like it calls for though. Thanks for your help
 

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Yes fully charged brand new battery. Tps volts in and out are at manual spec. The roll over has 5.+volts input at incoming wire KMS bypass just installed. The issue I see is that when I unplug the roll over and check volts I have proper 5v going towards sensor but I also have 3v showing up on the yellow/green coming from ecu. When I plug in original roll over or the KMS the volts on the y/g drops to .63v going back to ecu. To me it's seems like ECU is messed up
The test results on the Y/G wire are

unplugged 5v & with either KMS or down sensor installed 0.62v & the Y/G wire is now 3v... correct?

with the vehicle down sensor plugged in!...Did you get the same 0.62v whether you tilted it in the manual testing...???

Is your ECU (OEM stock)..?

It can be a bad ecu, bad connection/moister at the ECU connector into the harness...Try electronic cleaner or rubbing alcohol to clean the ecu pins & connector and see if you have the same test results..Caution don't damage the ECU pins

If so, I'd say it's the ECU..


Yes blue reference wire shows 5.2v with sensor plugged or unplugged. The y/g shows me 3.4v with nothing plugged in and then .62v when either sensor is plugged in. I checked/ blew out pins and no changes. I traced the y/g back to ecu to check for any worn spots and nothing. Ecu is stock as far as I am aware Only thing I noticed in my checking that didn't jog with the manual was in reference to ecu power source inspection page 3-65. Is there listing correct? Mine is opposite of what I calls for. I have battery v at terminal 13 key off and none at 29. Both have v with key on like it calls for though. Thanks for your help
Yea! Manual 3-65 is to test the connection for proper voltage to the ECU from the battery through the key switch...

ECU Power Source Inspection
Meter Connections:
Between Terminal 13 (W) and Battery (—) Terminal
Between Terminal 29 (BR) and Battery (—) Terminal
Ignition Switch OFF:
Terminal 13 (W): 0 V
Terminal 29 (BR): Battery Voltage
Ignition Switch ON:
Both: Battery Voltage

I'm suspecting your ECU is bad in the vehicle down circuit...should be 4.75~5.25 reference voltage not 3v...

The vehicle down sensor is only a variable resistor....!
 

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Discussion Starter #7
The test results on the Y/G wire are

unplugged 5v & with either KMS or down sensor installed 0.62v & the Y/G wire is now 3v... correct?

with the vehicle down sensor plugged in!...Did you get the same 0.62v whether you tilted it in the manual testing...???

Is your ECU (OEM stock)..?

It can be a bad ecu, bad connection/moister at the ECU connector into the harness...Try electronic cleaner or rubbing alcohol to clean the ecu pins & connector and see if you have the same test results..Caution don't damage the ECU pins

If so, I'd say it's the ECU..


Yes blue reference wire shows 5.2v with sensor plugged or unplugged. The y/g shows me 3.4v with nothing plugged in and then .62v when either sensor is plugged in. I checked/ blew out pins and no changes. I traced the y/g back to ecu to check for any worn spots and nothing. Ecu is stock as far as I am aware Only thing I noticed in my checking that didn't jog with the manual was in reference to ecu power source inspection page 3-65. Is there listing correct? Mine is opposite of what I calls for. I have battery v at terminal 13 key off and none at 29. Both have v with key on like it calls for though. Thanks for your help
Yea! Manual 3-65 is to test the connection for proper voltage to the ECU from the battery through the key switch...

ECU Power Source Inspection
Meter Connections:
Between Terminal 13 (W) and Battery (—) Terminal
Between Terminal 29 (BR) and Battery (—) Terminal
Ignition Switch OFF:
Terminal 13 (W): 0 V
Terminal 29 (BR): Battery Voltage
Ignition Switch ON:
Both: Battery Voltage

I'm suspecting your ECU is bad in the vehicle down circuit...should be 4.75~5.25 reference voltage not 3v...

The vehicle down sensor is only a variable resistor....!


my reference to 3-65 is right from the ecu plug with out it plugged into the ecu it self. The w wire terminal goes directly to the main 30 amp fuse so I don't see how the manual is correct. The brown comes from the ignition switch. So following the wires and the diagram all mean mine is correct but the description in the manual of.
Ignition Switch OFF:
Terminal 13 (W): 0 V
Terminal 29 (BR): Battery Voltage
Ignition Switch ON:
Both: Battery Voltage
Seems wrong to me unless im missing something?
My reference voltage on blue roll over input is correct at 5.2 its just this mysterious 3v on the y/g feeding the roll over sensor that has me lost and leading to bad ecu.
 

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Yes blue reference wire shows 5.2v with sensor plugged or unplugged. The y/g shows me 3.4v with nothing plugged in and then .62v when either sensor is plugged in. I checked/ blew out pins and no changes. I traced the y/g back to ecu to check for any worn spots and nothing. Ecu is stock as far as I am aware Only thing I noticed in my checking that didn't jog with the manual was in reference to ecu power source inspection page 3-65. Is there listing correct? Mine is opposite of what I calls for. I have battery v at terminal 13 key off and none at 29. Both have v with key on like it calls for though. Thanks for your help
Yea! Manual 3-65 is to test the connection for proper voltage to the ECU from the battery through the key switch...

ECU Power Source Inspection
Meter Connections:
Between Terminal 13 (W) and Battery (–) Terminal
Between Terminal 29 (BR) and Battery (–) Terminal
Ignition Switch OFF:
Terminal 13 (W): 0 V
Terminal 29 (BR): Battery Voltage
Ignition Switch ON:
Both: Battery Voltage

I'm suspecting your ECU is bad in the vehicle down circuit...should be 4.75~5.25 reference voltage not 3v...

The vehicle down sensor is only a variable resistor....!


my reference to 3-65 is right from the ecu plug with out it plugged into the ecu it self. The w wire terminal goes directly to the main 30 amp fuse so I don't see how the manual is correct. The brown comes from the ignition switch. So following the wires and the diagram all mean mine is correct but the description in the manual of.
Ignition Switch OFF:
Terminal 13 (W): 0 V
Terminal 29 (BR): Battery Voltage
Ignition Switch ON:
Both: Battery Voltage
Seems wrong to me unless im missing something?
My reference voltage on blue roll over input is correct at 5.2 its just this mysterious 3v on the y/g feeding the roll over sensor that has me lost and leading to bad ecu.

Here's the color coded schematic see below
..
 

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Discussion Starter #9
Here's the color coded schematic see below
..[/QUOTE]

Yes but if you look at the white wire coming from pin 13 it goes directly to the main 30 amp fuse. Which would provide constant power unless bad fuse of course. But the doesn't match what the manual states as it says it is controlled by the switch. I'm just trying to make sure I'm not seeing this wrong and don't have a different issue before trying a ECU.
 

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Here's the color coded schematic see below
..
Yes but if you look at the white wire coming from pin 13 it goes directly to the main 30 amp fuse. Which would provide constant power unless bad fuse of course. But the doesn't match what the manual states as it says it is controlled by the switch. I'm just trying to make sure I'm not seeing this wrong and don't have a different issue before trying a ECU.[/QUOTE]


Not sure why the manual would say with the ignition switch off 0 voltage on the white pin 13, but battery voltage on the brown pin 29, key turned on Both battery voltage...If that was the case your lights would remain powered ON with the ignition key OFF... so your lights would work without the key turned ON...strange...!

I know the white wire from the solenoid feeds the rectifier & ignition switch (line side)...

Then both the white & brown wire (load side of the switch...branch off...the white wire then feeds the fan/relay, fuel pump/relay & ECU
the brown feeds everything else (battery voltage)..!!

Thus your fuel pump primes & your ECU is powered w/key turned ON...!!

My guess it's a miss print in the manual
 

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Discussion Starter #11
Here's the color coded schematic see below
..
Yes but if you look at the white wire coming from pin 13 it goes directly to the main 30 amp fuse. Which would provide constant power unless bad fuse of course. But the doesn't match what the manual states as it says it is controlled by the switch. I'm just trying to make sure I'm not seeing this wrong and don't have a different issue before trying a ECU.

Not sure why the manual would say with the ignition switch off 0 voltage on the white pin 13, but battery voltage on the brown pin 29, key turned on Both battery voltage...If that was the case your lights would remain powered ON with the ignition key OFF... so your lights would work without the key turned ON...strange...!

I know the white wire from the solenoid feeds the rectifier & ignition switch (line side)...

Then both the white & brown wire (load side of the switch...branch off...the white wire then feeds the fan/relay, fuel pump/relay & ECU
the brown feeds everything else (battery voltage)..!!

Thus your fuel pump primes & your ECU is powered w/key turned ON...!!

My guess it's a miss print in the manual[/QUOTE]

Yes it just seemed odd to me what the book was saying compared to what I was seeing and diagram. Ill get a ecu and post back my results. Thanks again for your help.
 

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Discussion Starter #12
Here's the color coded schematic see below
..
Yes but if you look at the white wire coming from pin 13 it goes directly to the main 30 amp fuse. Which would provide constant power unless bad fuse of course. But the doesn't match what the manual states as it says it is controlled by the switch. I'm just trying to make sure I'm not seeing this wrong and don't have a different issue before trying a ECU.

Not sure why the manual would say with the ignition switch off 0 voltage on the white pin 13, but battery voltage on the brown pin 29, key turned on Both battery voltage...If that was the case your lights would remain powered ON with the ignition key OFF... so your lights would work without the key turned ON...strange...!

I know the white wire from the solenoid feeds the rectifier & ignition switch (line side)...

Then both the white & brown wire (load side of the switch...branch off...the white wire then feeds the fan/relay, fuel pump/relay & ECU
the brown feeds everything else (battery voltage)..!!

Thus your fuel pump primes & your ECU is powered w/key turned ON...!!

My guess it's a miss print in the manual[/QUOTE]

Replaced ECU still same results. Any suggestions?
 

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Discussion Starter #15
I have no spray at injector on 3 second cycle. Has power, no ground.
The vehicle down sensor kills the spark & fuel when activated...!!! 3.7~4.4v DC normal operation range...![/QUOTE

That wasn't meant to be posted, I'm still showing 3.4 volts out of the y/g when down sensor is not plugged in then with sensor plugged in it drops to .62 still with another ECU plugged in. No idea what to do now
 

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I have no spray at injector on 3 second cycle. Has power, no ground.
The vehicle down sensor kills the spark & fuel when activated...!!! 3.7~4.4v DC normal operation range...![/QUOTE

That wasn't meant to be posted, I'm still showing 3.4 volts out of the y/g when down sensor is not plugged in then with sensor plugged in it drops to .62 still with another ECU plugged in. No idea what to do now
It's possible your vehicle down sensor & KMS eliminator might be bad...

It's also possible you have a bad down sensor circuit/harness..Can you test the resistance/OHMs of each wire of the down sensor...??

And can you find a known good vehicle down sensor to try (like from a running quad)...???
 

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Discussion Starter #17
The vehicle down sensor kills the spark & fuel when activated...!!! 3.7~4.4v DC normal operation range...![/QUOTE

That wasn't meant to be posted, I'm still showing 3.4 volts out of the y/g when down sensor is not plugged in then with sensor plugged in it drops to .62 still with another ECU plugged in. No idea what to do now
It's possible your vehicle down sensor & KMS eliminator might be bad...

It's also possible you have a bad down sensor circuit/harness..Can you test the resistance/OHMs of each wire of the down sensor...??

And can you find a known good vehicle down sensor to try (like from a running quad)...???


I don't believe either is bad, only reason saying that is if I don't plug either sensor and jump power from blue 5v into either sensor it shows the correct output voltage. All 3 of the down sensor wires ohm out fine. I did find a short in the rear reverse light harness, could that have possibly fried the first and second ecu to give me this 3.4v output on the Y/g? I hate to buy another ecu to try. I currently have every sensor, relay and plug unhooked from the harness except the white main 30 amp feed and key switch to power up ecu. Still same 3.4v at y/g
 

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It's possible your vehicle down sensor & KMS eliminator might be bad...

It's also possible you have a bad down sensor circuit/harness..Can you test the resistance/OHMs of each wire of the down sensor...??

And can you find a known good vehicle down sensor to try (like from a running quad)...???


I don't believe either is bad, only reason saying that is if I don't plug either sensor and jump power from blue 5v into either sensor it shows the correct output voltage. All 3 of the down sensor wires ohm out fine. I did find a short in the rear reverse light harness, could that have possibly fried the first and second ecu to give me this 3.4v output on the Y/g? I hate to buy another ecu to try. I currently have every sensor, relay and plug unhooked from the harness except the white main 30 amp feed and key switch to power up ecu. Still same 3.4v at y/g
Your quote from the previous page (Ecu is stock as far as I am aware)

Can you take a picture of your ECU & post it...I need to confirm it's OEM stock or other...!

Stock OEM pictured below
 

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Discussion Starter #19
It's possible your vehicle down sensor & KMS eliminator might be bad...

It's also possible you have a bad down sensor circuit/harness..Can you test the resistance/OHMs of each wire of the down sensor...??

And can you find a known good vehicle down sensor to try (like from a running quad)...???


I don't believe either is bad, only reason saying that is if I don't plug either sensor and jump power from blue 5v into either sensor it shows the correct output voltage. All 3 of the down sensor wires ohm out fine. I did find a short in the rear reverse light harness, could that have possibly fried the first and second ecu to give me this 3.4v output on the Y/g? I hate to buy another ecu to try. I currently have every sensor, relay and plug unhooked from the harness except the white main 30 amp feed and key switch to power up ecu. Still same 3.4v at y/g
Your quote from the previous page (Ecu is stock as far as I am aware)

Can you take a picture of your ECU & post it...I need to confirm it's OEM stock or other...!

Stock OEM pictured below
Yup it's the same.
 

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Your quote from the previous page (Ecu is stock as far as I am aware)

Can you take a picture of your ECU & post it...I need to confirm it's OEM stock or other...!

Stock OEM pictured below
Yup it's the same.
Ok..Can you do a Self diagnostic to check for DFI errors...?

Just to see if anything else hows up...?

There's an orange wire in a black pouch under the hood...ground the orange wire to the frame & turn on the key...the F.I light will blink if any codes are present...!

See pictures below...
 

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