Hi @maggiez ,
Check that the alternator is charging the battery correctly.
Use a DMM’s (digital multimeter) DC Voltmeter function to measure the voltage across the car’s battery terminals. Do this with the engine running.
It should measure in the range 13.8VDC-14.5VDC.
Anything less than 13.8VDC means that the battery is not being charged when the engine is running.
Not sure regarding your vehicle whether the voltage regulator (controls the output from the alternator) is inbuilt in the alternator or whether it is a separate component.
BE SAFETY AWARE when you do this check as the engine is running when you are testing the charging voltage at the battery terminals. Ensure that the vehicle is in park or neutral and that the emergency brake (aka handbrake or parking brake) is firmly applied. Watch where you place your hands and check that your clothing (or hair?) doesn’t get caught up in the moving parts of the engine.
If you don’t have a DMM or know someone who does, go to an auto electrician or a car battery supplier and get them to check it for you.