Hi all,
hope you can enlighten me a little here. I have a 2011 mazda sp25 that has a slight electrical issue. I believe it maybe an alternator but want to know peoples experience here. What happens to the infortainment so to speak is sometimes it is running but then it will turn off and the air conditioner loses the cold air with just the fan running and radio gets a clicking sound and you can not access the infotainment. A car restart sometimes fixes the issue.
I have tested the voltage of the alternator when its just turned on and it is 13.6Vand when connected to a new battery (only 3 days old) the steering etc is no problem. BUt when i start the car and then disconnect the battery and let the alternator continue to run the car only it barely is able to keep it running. When i turn the steering wheel with just the alternator powering the car the power steering jitters, it can not supply enough power to run the power steering pump on its own and when testing the voltage across it during the movement of the steering wheel it drops to like 8 - 10 v is this normal for an alternator to be working like this.

In my previous cars an alternator has always been able to run the car once tha car is running but my mazda has no hope and will stall the engine if i try and turn the steering wheel only.

 

Never try & run a modern car without the battery connected, you are risking alot of delicate electronics.

What I would do is buy a voltmeter that plugs into the cigarette lighter socket & monitor it while you are driving. See if the voltage drops sharply while you are driving.

 

to me this seems like a poor engineering design because if the battery fails (or a connection to the battery) then I can see this being very dangerous and easily will cause an accident. I'm surprised a 100Watt alternate can not keep a car running.