If you have a problem with the starter not working, it could be the start relay wiring causing it, see other thread.To test, first of all bridge across from the top large terminal to the small spade terminal on the end of the solenoid. This should make the solenoid pull in and the starter turn the engine. If this works, but pressing the starter button rarely does, then refer to start relay wiring thread. If nothing happens, then you probably have a faulty solenoid, continue to the next part.Next bridge across the two main terminals on the end of the solenoid. This should spin the motor but won’t engage it with the engine. If nothing happens, you have a faulty starter motor. If the motor spins, but didn’t in the first test, then you have a faulty solenoid.A large screwdriver or similar is best to use for bridging, just be careful not to touch the frame or an earth at the same time. You will see sparks, this is normal.