Starter Solenoid

A single click with no cranking often points to the solenoid or poor connections. It is usually replaced together with the starter motor. Start-stop cars use reinforced starters and solenoids. Measuring voltage at the solenoid terminal while someone turns the key shows whether the start signal arrives. If the signal arrives but the starter does not turn, the solenoid or starter is the likely cause.

A small current from the ignition circuit energises the coil, which pulls a plunger that engages the pinion and closes heavy contacts.

Worn solenoid contacts can cause intermittent no-crank problems. Disconnect the battery before working on starter wiring.