Mk4 ND runs cold according to temp gauge

  1. My model of MX-5 is: __2016 Sport Nav 2.0l
  2. I’m based near: __Gloucester
  3. I’m looking for technical help or recommendations on: __my mk4 ND, which runs cold according to temp gauge, the needle never moves into the ‘normal’ sector. Is this ‘normal’ / OK ?

Which temperature guage is the screen showing, is it the 50 to 130 scale with the red and blue sectors, or is it the 100 to 120 scale?

There is a button at the at the top of the instrument display that swaps between the 2 gauge types, the 50 to 130 one is the standard scale.

Now that’s a good question. I only took delivery of it on Saturday and I’m still getting to grips with the displays and options. I will check later today and come back. Many thanks for the tip,

Hello again, this is the diagram in the user guide, The needle never gets past 100 and I’m assuming running temp should be around 110 even at this time of year. Not checked the car’s gauge yet.


110 seems a tad high to me.
100, as we all know, is normal boiling point for water at sea level. The cooling system is pressurised, which raises the boiling point and the coolant mix raises it some more with the combined effect raising the boiling point to around 130c.
If the Mazda coolant pressure is higher than most, that could be higher though.
My 3 series runs at a rock solid 100c but I think that’s for oil, so maybe coolant temp is a little higher.

That’s the 2nd gauge. If you press the control stick thing should revert to the 0 - 100 scale

The temperature is normally just below 100, the first gauge never moves on the scale.

The second guage is the normal one, and you can seen the button in the pictures.

Pictures of the two gauges below.

Hi C,
It may be that your car does not have the dual read out. My ND1 did not and ND2 does.
100c or better just under sounds right to me. You quote the normal sector and I think this is the area below 100c. Anything over 100c is too hot in normal running and would be something to watch.
If you are concerned buy or borrow an OBD reader and it will show the exact temperature of the cooling system.
If your heater is blasting hot air out then I think your car is normal.

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2016 car won’t have the dual display option. My 2017 doesn’t. The temperature reads just under 100, all the time. I have not had any cooling system issues including when climbing the Stelvio and various other Alpine passes.

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Yep the ND1 doesn’t have the dual temp gauge. My 2018 doesn’t have it.

Many thanks all. Your great answers have beautifully answered my query.

If my memory is correct, the updated display first appeared with the RF and was added to the soft top with the ND2 update.

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Sounds about right, guess I’ve got an ND 1. Thanks, all

Sorry I’m a bit late to the party @KJ-MX5, but I can confirm that my 2017 ND1 RF 2.0 does have the dual temp gauge scale :slightly_smiling_face:

…never had any car go much past 90? (temperature)…

Normal on my 320d is 100c but that is oil temp.
Once there, it stays rock solid