Boliy (BOLYJ07.4) Engine Speed Controller

Check the resistance of the economy switch using an ohmmeter. Once the stepping motor controller is checked, the generator should be checked. A controller with 14 volts DC should supply electricity to the wires that carry the black and red signals. In the case of a bridge rectifier that does not have 14 volts, it should have two yellow wires linking it to the power source. There may be a problem with the stepping motor on top of the carburetor if you have 14 volts from a controller. Here's what I came up with.

If you are stuck on idle speed it may be caused by 2 common problems. The most likely problem is the rectifier supplying the 14V DC to this controller is damaged. If the voltage coming from the rectifier is 14 V DC, the rectifier is working.