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Discussion Starter · #1 ·
Okay, so further trouble shooting revealed my fan actually does work, but only with the AC turned on. This gets me looking at 2 items:
1) Thermostat (I think it's running hotter than normal, but honestly I hadn't been paying attention so i don't even recall where normal is - i run pretty much dead on 1/2 way between hot and cold)
2) Coolant temp sensor

Is there a way to test the temp sensor with a multimeter or something to know if it's bad? Also, anyone got a pic of where it's located specifically? Which of these would you replace first if there's not a way to confirm that the problem is the sensor?
 

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I feel like mine doesn't work either, but it's also kinda hard to get ours up to 220 degrees to begin with. I've only got it up there once when it was 110 degrees outside and not moving in traffic... and then it started to go down; but I still can't hear my fan, and to lazy to let my car idle at home and pop the hood open just in time.

but supposedly it's 220


The water temp gauge though isn't going to let you know at all how hot you're running (as in you won't see any difference between normal good running temps and 220)

Our gauge starts to move when it gets up to 120 degrees F but around normal running temps which is like 170 it's all pretty bland on the water temp gauge; I am tracing mine with a gauge that plugs into OBD2
 

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Discussion Starter · #8 ·
Wish that was the case - this whole investigation was initiated by a CEL that indicated coolant temperature insufficient. Plenty of fluid. I guess i need to do the most simple test - get it up to temp and run to advanced to see if their scangauge tells me what temp my coolant is. Can anyone get a quick pic of their temp gauge during normal operation? From what i remember, mine ran around 3/8 up the gauge normally, im sitting much closer to 1/2 now.
 

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Mine is ALWAYS at the 1 below the middle point. The fan "should" kick in around 210-220 as most coolant/mix start boiling just above that. Running slightly at a lower temperature isn't really a problem.
I don't think the thermostat even fully opens below 180? can't remember the exact number.

I can usually hear the fan running after driving around in Oklahoma/Texas heat after I park. It stays on for another second after I turn the engine off.
 

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Discussion Starter · #10 ·
yea..see that's where my problem is - i hear what sounds like the module trying to keep the fan running after i shutdown...but the fan isn't moving. Like i said, im running spot on the middle mark or even 1 higher.
 

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I feel like mine doesn't work either, but it's also kinda hard to get ours up to 220 degrees to begin with. I've only got it up there once when it was 110 degrees outside and not moving in traffic... and then it started to go down; but I still can't hear my fan, and to lazy to let my car idle at home and pop the hood open just in time.

but supposedly it's 220


The water temp gauge though isn't going to let you know at all how hot you're running (as in you won't see any difference between normal good running temps and 220)

Our gauge starts to move when it gets up to 120 degrees F but around normal running temps which is like 170 it's all pretty bland on the water temp gauge; I am tracing mine with a gauge that plugs into OBD2
I wanted to make sure my new fan came on at the right temperature, so I disconnected the engine temperature sensor and hooked a 5K potentiometer to the connector going to the ECU to simulate the engine temperature to the ECU. This way I didn't have to get the engine actually hot to test the fan. I have an Ultra Gage on the OBDII connector monitoring the engine temperature. When I adjusted the potentiometer value lower, to get ~210 deg on the Ultra Gage, the fan started turning on. When I simulated ~230 it was running near full speed. As mentioned in some other threads, the engine temperature gage on the car panel doesn't follow the real temperature It stays around the middle until the temperature gets really high.
 
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