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Discussion Starter #1
my dealer says any time you roll the throttle backwards (mine has a good bit of slack that way)

it resets the ZERO on the ECM, and it now thinks when the throttle returns to rest, the throttle is being held open that much.

so at stop lights, you have to hold the throttle back to keep the idle down.

i was rolling the throttle backwards to turn off the cruise, i thought that was a real nice feature. gonna read the OM, see if it supposa work like that

here's the temp fix:
turn kill switch ON.
cycle ignitoon switch on long enough for light to go out.

4 times.


that resets it.

and it works fine till you go back ward again on the throttle


supposed to be a Re-flash to fix it,
but the service writer asked me to put this out to the forums, so folks won't be freaking out.
 

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Huh, I always disengage my cruise by rolling the throttle forward. Maybe I already had the update because I never have a problem with my idle.
 

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my dealer says any time you roll the throttle backwards (mine has a good bit of slack that way)

it resets the ZERO on the ECM, and it now thinks when the throttle returns to rest, the throttle is being held open that much.

so at stop lights, you have to hold the throttle back to keep the idle down.

i was rolling the throttle backwards to turn off the cruise, i thought that was a real nice feature. gonna read the OM, see if it supposa work like that

here's the temp fix:
turn kill switch ON.
cycle ignitoon switch on long enough for light to go out.

4 times.


that resets it.

and it works fine till you go back ward again on the throttle


supposed to be a Re-flash to fix it,
but the service writer asked me to put this out to the forums, so folks won't be freaking out.

That's a load of crap.. Rolling the throttle forward isn't going to fool the ECM into forgetting where 0 is at.

Granted the reflash of the ECM is probably the answer to the high idle conditions. But any notion that this is being created by the operator is pure B.S.
 

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If you don't have the update download, the operator can indeed cause the problem. It is caused by turning the bike off before it goes all the way back to idle, not by rolling the throttle forward. There is a FREE download from the dealer that fixes this known problem. The "roadside fix" of cycleing the ignition 4 times will also reset the throttle position.
 

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The problem is that when you roll the throttle forward and turn the ignition OFF, that resets ZERO throttle position in the ECM. That is why the temporary fix is cycling the igniton on and off four times. Best fix is prevent the problem in the first place by taking right hand off the throttle putting your right hand on the ignition and turn it off. If you use the kill switch you can also casue this promlem because as your thumb presses against the top of the kill switch your hand is naturally going to move forward thus rolling the throttle forward.
 

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You shouldn't have a problem with killing cruise by rolling the throttle forward, that is one of the features with cruise.
I have heard if you kill the motor at higher rpm than idle it will reset to the higher idle. Not sure if it is true or not.
 

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The problem is that when you roll the throttle forward and turn the ignition OFF, that resets ZERO throttle position in the ECM. That is why the temporary fix is cycling the igniton on and off four times. Best fix is prevent the problem in the first place by taking right hand off the throttle putting your right hand on the ignition and turn it off. If you use the kill switch you can also casue this promlem because as your thumb presses against the top of the kill switch your hand is naturally going to move forward thus rolling the throttle forward.
If you roll the throttle forward, that should be idle, right. How would that make the bike start at high idle?
 

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If you don't have the update download, the operator can indeed cause the problem. It is caused by turning the bike off before it goes all the way back to idle, not by rolling the throttle forward. There is a FREE download from the dealer that fixes this known problem. The "roadside fix" of cycleing the ignition 4 times will also reset the throttle position.
According the the Electrical manual. The Zero throttle position is only learned and written as a value when the ignition is turned on.
And that is independant of where the grip is.

There are a couple of conditions that will cause a fast idle and no code gets set unless the condition exists for at least 4 ignition cycles.

Would have to wonder what paramters the download is changing. Ie. when the bike goes into fast idle or limp home, will it throw a code on the first error?
 

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Rolling the throttle forward is closing the throttle. And from experiance the ZERO throlle position is written to memory when the ignition is turned off. When ignition is turned on it looks at memory and says ok that is where it was last time and since no one would turn the ignition off at anything other then idle that must be where it is again. And since the grip does control your throttle electronically its position does matter.
Also it does not take 4 times before it is written to memory, it takes four times to get it out of memory.
 

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Rolling the throttle forward is closing the throttle. And from experiance the ZERO throlle position is written to memory when the ignition is turned off. When ignition is turned on it looks at memory and says ok that is where it was last time and since no one would turn the ignition off at anything other then idle that must be where it is again. And since the grip does control your throttle electronically its position does matter.
Also it does not take 4 times before it is written to memory, it takes four times to get it out of memory.
Whatever you say man!!! If you read Harley's documentation on how this system works and this is how you interpret it, then party on!!!
Page 4-200 explains what happens at startup
Page 4-190 explains what happens when the Throttle is de-energized. Neither of these two situations state that they are reading the TGS sensors.

If you haven't read up on this, then you have proved my point that there is alot of B.S. floating around on how the TBW actually works.

I hope the download takes care of your problem.. Mine happens to be perfect and can't get all futzed up with charms, incantations and shutdown rituals. Nor does rolling the throttle forward do anything other than disengage the CC.
 

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Discussion Starter #13
dangit.

I reset my EITMS since it was hot, and that reset my Zero point.

so now, I have to hold the throttle all the way forward to idle at 1000 RPM.

gonna have to do the 4 ignition cycles to clear it,

i tried it at a stop light, but must have went too quick, because it idled at ~2000 RPM on my 15 minute ride to buddies house.

i've had the download done twice.
 

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Well, Blackdawg then you are not speaking from experiance as I am, so you just keep reading books and then when you get some practical experiance you will be a well rounded person, until then you only know the theory.
 

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Oh BlackDawg, I have read the 2 pages you referenced in your last post, and both pages are concerning potential fault codes that can be registered as failures and stored in the ECM.

If you were really as observant as you claim to be you would have noticed earlier in this thread that when the ZERO throttle position of the ETC is stored in the ECM it does NOT set a DTC. And if you were to read page 40 of your owners manual you would also learn the the ETC feed the ECM which them feeds the throttle body.

And I realize that using your hand to reach over and turn off the ignition is too complicated of a ritual for you to learn, so however you are doing it, I hope it continues to work for you.
 

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Hmm......I canceled my cruise that way on my '08 Ultra and I am doing it on my new '09 SG. No problems at all.
 

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Using the throttle to cancel you cruise control is not part of the problem.

The problem is rolling the throtlle forward and turning the bike off. When you turn the bike off the ECM stores the current position of the Electronic Throttle. This stored position is considered zero throttle control position by the ECM. So when you turn your bike back on the ECM sees that the throttle is not in the same position so it assumes that the rider has opened the throttle to the positive side of zero and thus adds more fuel to the cylinders, making the bike idle faster.
Since this is not a failure no DTC's are set. The bike is just doing what the rider has told it to do.

The rumor from HD is that they are going to delay shutting power off to the ECM by something like 10 seconds on the 08's via software, thus allowing for time for the rider to take his hand off the Electronic throttle and the springs in it zeroize itself. The 09's are supposed to come from the factory with this fix in place.
 

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I had this high idle gremlin strike recently and I never use the kill switch to shut down. I always let the idle stabilize and use the centre switch to turn off because I was aware of the problem. Happened one time only for no reason I can determine but the on/off cycle procedure worked to reset the idle speed. Go figure...
 

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Thanks,04ctd, I had this same problem and was about to call the dealer. I guess my hand may have rolled the throttle forward slightly as I was turning it off.
 

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#1 The kill switch is very handy, for reason. Why do people keep talking about using the kill switch causing a problem, which is right beside your thumb? Your throttle shouldn't move at all.
#2 Why do people think moving the throttle forward, which is idle position, has anything to do with it?

If you accidently goosed the throttle, roll it back, and killed the engine I could maybe see it changing the idle faster. But you would think doing it one time wouldn't change anything.
I'm not sure what the problem is, myself.
 
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