I have a 01 heritage EFI, 40k miles. I have had no problems with this bike til last night. With the switch in the off position the IAC continues to make noise, sounds like it spins up ever 15 seconds or so. The bike runs great, idles fine, but the only way to make the control stop is to un-plug the control or disconect the battery. Is there a test for the IAC or has anyone else had this problem. Is there something else that could be making this happen. I do my own repairs so I want to fix everything that needs to be fixed. Thanks

 

As far as I know it's controlled by the ecm so you ought to have a DTC code stored for it. As near as I can tell the ecm calibrates the IAC when you turn off the bike, either the kill or ignition switch. It closes all the way then backs out to a position appropriate to starting the bike. I assume it can't directly read the IAC position, but rather can tell when it isn't moving, i.e. current draw or something.

If you pull the ac and back plate you can see the hole for the IAC before the throttle plate at the top. You can use a mirror to sight up through that hole and see the pintel. If it's closed and not moving when you shut off the bike then it isn't working. You can pull it and see if there are deposits on the pintel threads or anything blocking the passage. It actually sounds a bit differant when the motor is running but the pintel isn't actually moving, there's a slight click to it. Someone said a new one costs about $45.

 

Oh yes, it should stop if you pull the maxi fuse as well. It shouldn't run when you put the fuse back in until you cycle the bike again.

 

that would make sense because when i pull the ground wire off the battery and put it back on it does'nt start to make the noise until i turn the switch to the on position. thanks for your knowledge.

 

LilBudyWizer, ok I looked at the pintel and it continues to go up and down, I took it out and it looks clean, I unscrewed the threads put it back to gather and no change. I would have been surprised if there would have. Anyway do you think it would be the ecm then, if thats the case I would have to have it programmed at a dealer right? I don't have a scanner of any kind. Any idea how much they cost?

 

They cost about $45. I'm reluctant to say it's the ecm. I'm inclined to believe the ecm is either going to work correctly or not at all.

 

Since you've unplugged the control and plugged it back in, it's probably not just a bad connection, which I would have checked first anyway.

There really just about has to be an error code over this situation. If the wiring/connectors is all intact it probably is the IAC itself which went south. I'm thinking there are control and report circuits involved. It sounds like the motor is getting what it needs both directions but the ECU isn't getting satisfactory report as to the position. It sounds like about the same thing happening when the lens on a CD/DVD reader gets dirty or the mechanism fails, and you stick a disc in, close the drawer, and hear the focus mechanism jacking the lens up and down to the limits trying to get a focused reading from the disc.

 

I know this is an oldy, but I'm

I have the same problem. My “IAC” on my Dyna keep calibrating every 30 seconds, even when the bike is switched of. I have a Street Bob 2014 and removed the “Ignition key switch” and I use the toggle switch (kill switch) to turn the bike off & on. The ECM is changed and knows the bike has no “Ignition key switch”. What has been done so far. 2 new “IAC” | completely new ECM | new voltage regulator | new Battery. If I store the bike for 4 days, the Battery is almost empty, and will hardly start. Because this 🤬 IAC keeps moving.
Any tips? I don’t know what to do anymore.

 

Delete

 

Delete