My son drives my 2015 mazda6. This car has 2.5 skyactiv engine. 70k miles. Reliable mostly.
Starting this week the car had the telltale sign of a dying battery (slow cranking then successive starts even slower) so I visited the FLAPS to have them test the battery and charging system. Their diagnostic test said the battery had a bad cell and the alternator is bad.
I bought a new battery and a reman alternator and called my buddy the mechanic who comes to my house.
He noticed the battery handle was smashed under the hold down clamp which deformed the caps on the battery - and it actually creased one side and eventually broke the top of battery case. So that's nice. And the battery was grossly undersized.
He asked me if the battery light had come on recently... It had not.
After putting in the new battery, he used a volt meter and noticed the startup voltage was right at 12.5 then after about five seconds after starting it ramped up to 14V charging. And held steady.
Is this normal behavior for a Mazda alternator and voltage regulator? Does it sound like a symptom of a bad alternator?
For the record I told him to get going and I will just return the alternator. But I wanted to ask the most knowledgeable auto message board on the planet. What say you?
