Engine won't crank unless.

Hi @shingo84992

Just curious as to why you're starting the engine with the lights on? This only puts an extra strain on the battery when starting.

Sounds as though there's a battery charging problem or just a battery problem.

Measure the charging voltage for the car's battery to see if it is being correctly charged or not.

With the car parked, the transmission in Park (AT) or Neutral (MT) and the parking brake applied turn on the engine and use a voltmeter to measure the voltage across the car battery terminals.

You should read 13.8V DC - 14.5V DC.

If the voltage is <13.8V the battery is not being charged correctly and if it is only being driven short distances every time, it will eventually lose charge to a point where it can't start the engine, regardless of whether the lights are on or not.

If it is <13.8V DC then it could be a faulty voltage regulator or alternator or even an incorrectly tensioned serpentine belt.

If the charging voltage is OK take the vehicle to a battery service centre and get them to do a deep discharge test on the battery to see if it is OK or not. It could be simply a case that the battery is failing. Most car batteries only last 4-5 years before needing to be replaced. Maybe it's giving you a warning that this may have to happen soon.

Be safety aware when you try this as the motor is running. Watch where you place your hands and if you're wearing any loose clothing etc. You don't want to get caught up in a turning motor.