AT light comes and goes. 2011 Mazda3

[Vamp_66]

Hi everyone,
My daughter reported to me that the AT light came on the dash while driving her 2011 Mazda3 with 118,000KM on the ODO.
She said the car did not make any strange shifting of gears while driving or noises from P to D at any time.

After some time, she restarted the car and the AT light was gone from the dash.
(I perform oil changes and ensure all fluids are topped up)
I should mention that a reputable garage checked the trans fluid, put his code reader on it and nothing showed...

Being unable to get my code reader on the car while the AT light was on makes it difficult to diagnose the issue.
However, the forums are full of issues regarding the TCM or TSS sensor...but on older models such as '06's.
Wanting to solve this issue from reoccurring and not wanting to cause any damage in the future, (possibly leaving her stranded somewhere) is it advisable to swap out the TCM anyway?

I'm kind of lost on this one...
If it matters I'm in southern Ontario and the temperature today was -6C.
Any help is greatly appreciated
Cheers,
Ed

[Flagrum_3]

Hi everyone,
My daughter reported to me that the AT light came on the dash while driving her 2011 Mazda3 with 118,000KM on the ODO.
She said the car did not make any strange shifting of gears while driving or noises from P to D at any time.

After some time, she restarted the car and the AT light was gone from the dash.
(I perform oil changes and ensure all fluids are topped up)
I should mention that a reputable garage checked the trans fluid, put his code reader on it and nothing showed...

Being unable to get my code reader on the car while the AT light was on makes it difficult to diagnose the issue.
However, the forums are full of issues regarding the TCM or TSS sensor...but on older models such as '06's.
Wanting to solve this issue from reoccurring and not wanting to cause any damage in the future, (possibly leaving her stranded somewhere) is it advisable to swap out the TCM anyway?

I'm kind of lost on this one...
If it matters I'm in southern Ontario and the temperature today was -6C.
Any help is greatly appreciated
Cheers,
Ed

If an actual code was spawned, I believe it would have stayed in memory and your mechanic would have picked it up. Since there were none and no symptoms involved, it leads me to believe it was just a phantom code, or a glitch. I've had a couple over the years. I would just keep a keen eye on it, maybe change out your transmission fluid if you haven't in a while.

_3

[Vamp_66]

Thank you for the feedback...
Makes sense. I wasn't with the vehicle when the garage hooked up the reader and thought the same thing. I'll plug in my reader and see if it's still there.
As for changing the trans fluid on a Mazda 3, is it as simple as removing the drain plug, drain and fill?
On my civic it is just that simple - faster than doing an oil change!
Thanks again,
Ed

[Flagrum_3]

Thank you for the feedback...
Makes sense. I wasn't with the vehicle when the garage hooked up the reader and thought the same thing. I'll plug in my reader and see if it's still there.
As for changing the trans fluid on a Mazda 3, is it as simple as removing the drain plug, drain and fill?
On my civic it is just that simple - faster than doing an oil change!
Thanks again,
Ed

If you have a code reader, leave it in the glove box and show your daughter how to use it. If a code pops up again, then she can scan it immediately. As for the fluid change, I personally have never done one on the Mazda auto, but I would suspect its as simple as drain and fill, but then I seem to remember something about having to remove the pan.. Maybe someone else can chime up here and verify it.


_3