The blue light will come on. That is the indicator telling one to pull over.
Cx-5 2017 ac
- Thread starter laf
- Start date
The blue light will come on. That is the indicator telling one to pull over.
Blue means cold and red means hot.
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- 2022 2.5GT
Now we’re getting somewhere. “The response is none linear”.
I’m sorry, I can’t handle your strange units but if we use a normal scale where 0 is freezing and boiling is 120 (achievable by having a pressurised cap otherwise it would of course be 100), then normal on an unmarked gauge is going to be dependent on the thermostat. On ours, it opens at 88C and is fully open by 100C. That means “normal is going to be in that range and the 195F recorded on the OBD is 90.5C - exactly what I would expect. It also means that there are 90 degrees to the left of normal and 30 to the right so the scale changes. Those fluctuations seen in jthj’s experiment on a scale of 32-250F are not going to show - a needles width is probably 20F but if the temperature shifted enough, the gauge would respond.
I’m sorry, I can’t handle your strange units but if we use a normal scale where 0 is freezing and boiling is 120 (achievable by having a pressurised cap otherwise it would of course be 100), then normal on an unmarked gauge is going to be dependent on the thermostat. On ours, it opens at 88C and is fully open by 100C. That means “normal is going to be in that range and the 195F recorded on the OBD is 90.5C - exactly what I would expect. It also means that there are 90 degrees to the left of normal and 30 to the right so the scale changes. Those fluctuations seen in jthj’s experiment on a scale of 32-250F are not going to show - a needles width is probably 20F but if the temperature shifted enough, the gauge would respond.
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- RDX Aspec Adv.
Having owned vehicles that had real gauges, I strongly disagree. My Z06 would show coolant as well as oil temps digitally to the very degree, and they fluctuated depending on speed, acceleration, temp during the commute, all manner of things.
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- RDX Aspec Adv.
Exactly. It's a family car with an idiot light. Thank-you for doing this so that at least MOST of the people on this board can be satisfied, lol
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- RDX Aspec Adv.
The light will come on and the needle should rapidly move to the red before anything is truly destroyed. Same for your oil pressure (although even with real gauges, that changes FAST). I get such a laugh out of those gauges. Sits right in the middle, lol! Idle or WOT.
Yes but that was a sports car. Here most vehicles as in family cars only had temperature and fuel gauges and as mentioned, temperature gauge didn't move that much. I'm talking family cars here from 1970s and 1980s.
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- RDX Aspec Adv.
I have no experience, there. That said, I find it hard to believe that a car with a liquid/liquid cooler that stabilizes oil and coolant temps against each other would be somehow MORE prone to fluctuate. That said, 80's vs. 2011 tech. Also, sensor fidelity, etc. I dunno.
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- RDX Aspec Adv.
A WOT pull through some gears would bump the 11 quarts of oil up by about 10 degrees in my Z06, just a quick romp through 1st and second and part of 3rd.
I can watch oil temp as well. I know on my ST there wasn’t actually a sensor for oil temp rather it’s inferred from coolant and other data available to the ECU. I’m guessing that’s probably the same in the Mazda as well. I do notice that on my VW GTI when I pull up the oil temp gauge I do see a similar behavior to what you’re describing.
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- 2022 2.5GT
I wasn’t “arguing the point”, I prefer to think we can have a debate - a bit like those boffins that sit in front of a live audience and talk about the origins of the universe.
You can’t really compare older cars with newer cars. The CX-5 has a radiator shutter and enough electric fan power to create a fair ram air effect on the radiator. Its much more capable of regulating temperature. Diesels engines are so slow to warm up that the diesel CX-5 has a PTC heater in the climate control to electrically heat the interior during warm up. The temperature climbs gradually up to normal some miles after starting. It doesn’t index to pre determined marks. I know full well the needle doesn’t climb above half way because I was watching that rental I had on the journey to Key West and back. However, I’m thoroughly convinced that if I interfered to artificially rig the cooling system by either locking the shutter shut or disconnecting the fan that it would continue to rise. I’m not sure you would get anywhere by thrashing the engine as the fan would take care of that together with the increased airflow but you could try it.
You can’t really compare older cars with newer cars. The CX-5 has a radiator shutter and enough electric fan power to create a fair ram air effect on the radiator. Its much more capable of regulating temperature. Diesels engines are so slow to warm up that the diesel CX-5 has a PTC heater in the climate control to electrically heat the interior during warm up. The temperature climbs gradually up to normal some miles after starting. It doesn’t index to pre determined marks. I know full well the needle doesn’t climb above half way because I was watching that rental I had on the journey to Key West and back. However, I’m thoroughly convinced that if I interfered to artificially rig the cooling system by either locking the shutter shut or disconnecting the fan that it would continue to rise. I’m not sure you would get anywhere by thrashing the engine as the fan would take care of that together with the increased airflow but you could try it.
I feel like I’ve offered proof that it does artificially go to the middle at a temperature labeled that doesn’t correlate to actual readings.
Do you have any counter evidence either documentation that it’s supposed to be an accurate real time readout or evidence from observation?
My opinion here is that the cooling system while it’s great and all can’t just instantly react and hold the temp precisely. And honestly that isn’t even necessary. It’s quite normal to fluctuate within a safe range. They just don’t show this to the end consumers as it’s 1 not necessary and 2 just tends to lead to people worrying because it went up a bit when they climbed that hill or whatever and complain when it’s all perfectly normal and nothing is wrong.
And as others have said pretty much ALL modern cars do it and a lot don’t even bother with a gauge at all.
Do you have any counter evidence either documentation that it’s supposed to be an accurate real time readout or evidence from observation?
My opinion here is that the cooling system while it’s great and all can’t just instantly react and hold the temp precisely. And honestly that isn’t even necessary. It’s quite normal to fluctuate within a safe range. They just don’t show this to the end consumers as it’s 1 not necessary and 2 just tends to lead to people worrying because it went up a bit when they climbed that hill or whatever and complain when it’s all perfectly normal and nothing is wrong.
And as others have said pretty much ALL modern cars do it and a lot don’t even bother with a gauge at all.
In theory it should
