A Yamaha four-stroke that idles roughly or hunts for revs right after the throttle body was cleaned, or after the battery was disconnected or replaced, is often not broken at all. The control unit has lost or outdated its idea of where the throttle valve is closed and what idle needs. The app can teach this again, and for that situation it works well. Outside it, the relearn does very little.
The cases where it helps
The app offers two functions: learning the idle and learning the throttle valve. The app only shows the functions your ski actually has, and they matter most on the electronic throttle models, which means the VX1100 of 2005 and the machines that followed it.
The typical triggers are straightforward. You cleaned the throttle body and the valve now sits slightly differently. The battery was disconnected for the winter or replaced. A throttle body or sensor was changed. In each case the stored values no longer match the hardware, and the ski idles too high, too low, or stumbles when you let off the lever. Teaching the idle and the throttle valve aligns the control unit with what is actually there.
The cases where it will not help
A relearn is a calibration. It adapts the control unit to the hardware as it is, and it does not repair the hardware. If the idle is unstable because of a worn part, you can run the learning as often as you like and the symptom will return.
- A sensor with a bad contact will still jump after it has been taught. The pairs of TPS and APS values need to be steady before anything gets calibrated.
- Air leaking into the intake or a loose hose clamp changes the idle in a way the learning can only partly cover.
- A weak battery that sags at cranking is a voltage issue, and teaching does not change it.
- A stored fault code that is still active needs attention first. Clear and teach only after the cause is dealt with.
The practical order is to read the fault memory and look at the live values before you teach anything. If the values are steady and the memory is clean, the relearn is a sensible step. If they are not, fix that first. On the GP1300R, which has a stepper motor for idle and a throttle sensor that must read closed at start, a poor sensor contact is the more common reason for rough idling, and relearning will not touch it.
The SCU learning is a separate thing
RiDE models with the shift system (the SCU) have their own initial learning in the app. It is not part of the idle or throttle routine and is meant for the occasion when the SCU has been replaced. It is not a fix for a reverse gate that sticks or a strap pulled across the stern. If a RiDE ski reports a code such as 159, check the boring causes first: a strap, a bent rod, the harness plug, the relay and fuse, and the cable adjustment.
Where to find it
The Yamaha version of the M-JET Diagnostic offers the idle and throttle learning on the supported models that have them. The pages teaching the idle and SCU initial learning for RiDE describe the procedures.
Repair first, relearn second, and read the live values both before and after so you can see that something actually changed.
