volt meter across the battery not running will measure the battery voltage (about 12-13v)
volt meter across the battery car running will measure the charging voltage (about 14.1V)
voltmeter across the battery car running with lots of electrical load (lights heater fan demists) (about 14.1v) should not varry with engine speed
anything over 13.8v will be able to charge a lead acid battery
volt meter across the battery car running will measure the charging voltage (about 14.1V)
voltmeter across the battery car running with lots of electrical load (lights heater fan demists) (about 14.1v) should not varry with engine speed
anything over 13.8v will be able to charge a lead acid battery