if while driving the battery dies in the keys, would the car stall???
I was told this is what happen to me yesterday, my car just stalled all the lights on the dash lite up, and the car refuse to start the steering locked up.
A dead key battery will not cause the engine to stall. Do you have a proximity key or a conventional key with a metal blade?
Hi thank you so much for your response, no proximity key, did I mention the car is push start.
I got the car back today and the only thing that was done was a new battery for the key, and I was told because the battery died in the keys the car couldnât sense the key. Causing it to stall, I donât want this to happen again it happened in the middle of the highway rush hour traffic, and I had to be wrecked.
Any idea what may have caused it???
Who said that the key battery was the problem ? I know of people with proximity keys that have started the vehicle and drove off without the key. The vehicle ran fine but just would not start after they shut it off . As for the steering, it did not 'lock up â you just lost the power assist which just made the steering wheel more difficult to turn.
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The auto shop I took the car to said the key battery was the only problem they saw, that could of caused the problem.
So clearly looks like I need a second opinion.
Thank you for your time.
Unfortunately, the guy that told you that was clueless
You could take out the key fob battery, and the car would still start
Could be any number of things, such as a failing fuel pump, bad crankshaft position sensor, and so on
Just how much did they charge you for this low-quality observation?
I suspect whoever you dealt with had absolutely no idea how to diagnose no-start/stall problems that donât generate a fault code . . . aka weak diagnostic skills 
They probably didnât do any testing beyond scanning for codes, and they probably never bothered to look for any technical service bulletins or anything on their professional information website(s)
Yeah, you definitely need a second opinion
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The key fob is only needed to start the car, not to keep it running. In fact, a valet drove off with my Mazda3 once with the fob in my pocket. If the key fob battery dies you can still start the car by holding the fob, with the dead battery, up to the start button (right on top of it) and pressing the start button.
Your car will also warn you when the fob battery is low. A message comes up on the dash right as you start the car. FYI, this is all in your ownerâs manual, which I suggest you read through. If your manual is lost, Mazda posts all their manuals online.
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That is what they said, can you test it by removing the battery while it is running?
What happens when the battery in the key fob is really dependent on the car and how its computer software is written. I donât know if there are any âstandardsâ for these situations, but how one model behaves is not necessarily indicative of how an other one will behave.
I would tend to doubt that the key fob was the cause of the stalling since stopping the engine like that creates a potentially dangerous situation. Regardless, Barkydogâs suggestion is a good one - either remove the battery from the key fob while the engine is running, or simply hand it to someone outside the car and drive off. If you are ever in the situation where your key fob battery has died, all of these systems have a mechanical key backup system that lets you unlock the door and start the car. Check your ownerâs manual.
You didnât say much about the stalling problem - has it recurred now that you have a new battery in the fob? when did it occur - when stopped at lights, while you were driving, when parked? were you always able to restart the car? Most cars with these systems also have a warning for a low fob battery - did you get any such warning?
Hi P_in_Mpls,
No it has not stalled since the key battery replacement.
The stalled occur on the freeway rush hour traffic, while driving, car came to a complete stop. It was terrifying.
No I could not restart the car.
The key fod warning never came up individually, it illuminated with all the other indicates when the car first stalled.
When the car was finally wrecked the only two lights that remained on was the oil and battery.
So I would go back to the recommendation to try pulling the battery out of the fob when you are in a safe place to see if it indeed stalls. If thatâs the case, I would call it a design defect, as the ânormalâ operation of the car potentially puts the driver in a dangerous, even life threatening situation.
Also, find out where the mechanical key is, so you know how to use it if the FOB dies on you in a dark parking lot somewhere.
I dunno, Iâd take a look at the owners manual to see what it says but I doubt it would cause a stall. Yesterday in my Acura I got the message that the fob battery was low. Everything worked fine and when looking in the manual there was a procedure if the fob failed. Had to really look on the CD to figure out how to open the thing for a new battery.
If the key battery were dead of missing before starting the engine, when should the engine stall? Two minutes? Five minutes? It shouldnât, you can drive the vehicle with a dead key battery. The owners manual shows how the start the engine with a dead key battery.
my wife drivers 2013 Mazda3 and when she puts her bag with keys down to passenger leg area, car regularly tells âlost communications with keyâ or such, but keeps going just fine
2013 is the same model line as OPâs 2012 Mazda3