I have a friend's 04 RK in my home workshop with a bizarre issue. When the ignition and on/run switches are OFF the fast idle solenoid cycles repeatedly. First thing I did was try to see if it would give me a code. Not only is there no code (no check engine light either) but the speedometer needle does not cycle like it should when first retrieving any codes. There is a constant 10.5 volts going to the solenoid with both switches off (again is this normal?) So with all this in mind is it possible that there may be a wire or connector issue somewhere or does it seem that the ECU has bumed out? Just a small history also, this bike is a 04 RK that is a bone stock unmolested ride with 27,000mi. It has been sitting for 5 years untouched but ran fine then. Thanks for any input and suggestions.....peace.

 

TP sensor is probably bad. The IAC is closed at zero throttle, if the sensor is fluctuating it will cause the IAC open and close rapidity. (Sometimes stall coming to a stop).

 

Go through and check for corrosion on the ecm plug and all the fuses and relays. 2007 sportsters had an issue with the IAC cycling when shut off and killing the battery at night and corrosion in the fuse box was the cause.

 

With all the power off - can't be the TP sensor. Something is causing power to be applied to the circuit if it's operating with the bike off.

 

I missed the part where the ignition and run are off. I agree with Joe. Corrosion at a connector or a short in a wire

 

Power is supplied to the IAC when power is shut off. It is applied long enough to park it. If it is having problems getting to it's parked position it will keep trying. Several reasons this can happen. Checking corrosion on pins and connectors, and clean the IAC is where I would start because it can all be done for free.

 

The ECM doesn't know where the IAC is. It just sends a command. The power is not constant after the main relay and system shut down.

 

I am under the understanding that the ECM sends the command after shut down, and if the ECM doesn't think that the command was received. It will keep trying. It does this as a reference to know where the IAC position is, so it can put it where it needs to be for the start IAC position.

 

The ECM doesn't know where the IAC is. That's why there is a loss of idle speed control code and one of the first checks for that is a visual look at the IAC for movement at key up and shut down.

 

Thank you all for your thoughts on the issue. From what I gather nobody seems to believe it's a serious issue so for now I'll be cleaning connections, pins, ground points and looking for wire pinches. Thanks again and I'll be sure to post the results.....hopefully good results.