So, the car starting system includes; the battery, starter motor, solenoid, ignition switch, neutral safety switch and in some cases, a starter relay.
All internal-combustion engines, cannot start by themselves. Consequently, they all need, external help.
As a result, something has to set the engine in motion, before it can power itself.
So, car starting system problems, are common and not all of them, are caused, by a faulty starter motor. Proper testing is usually the only way to find the cause of the problem.
Starting The Engine
When you turn the ignition key to the START position, or press the START button, the battery voltage; goes through the starter control circuit and activates, the starter solenoid. Then, the starter solenoid powers the starter motor. At the same time, the starter solenoid; pushes the starter gear forward, to mesh it with the engine flywheel or flex plate. As a result, the starter motor spins, turning over the engine crankshaft, allowing the engine to start.
Neutral Safety Switch
For safety reasons, the car starting system, can only be operated; when the automatic transmission, is in the Park or Neutral position. Manual transmissions, have a different component, that acts in a similar manner, as the neutral safety switch.
This component is also, part of the manual transmission. So, to start the engine you have to depress the clutch pedal. A broken or failing neutral safety switch, can cause a myriad of problems. If your engine only starts in neutral; but not park, or only park, but not neutral, this could be the culprit.
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