how to check for engine fan running?
 

Is there a tried and true method for checking to see if the engine fan is running?

About 1,000 miles ago I removed the radiator and fan to replace the CPS o-ring and replace the fan low speed resistor. While it was apart I cleaned everything, flushed the radiator and refilled the system with a 50/50 mix of MINI coolant and distilled water, with a pint of RedLine Water Wetter.

Now the water temp gauge rises to the 12 o'clock position (I have Chrono package) when warming up and moves very little from there. I have even been caught in Atlanta bumper to bumper traffic a couple of times with no problems and very little needle movement.

The thing is, I have not heard the fan run in that time and I would think I would have at least once. Does anyone have any suggestions?

If you want to test the low and high speed fan you can just use the plug on the wire harness that you took apart when you removed the radiator before.

The wire harness has three wires. ground, low and high. Just unplug the connection and use 2 wires and jump to a power source like the battery. You can hear the difference between low and high speed fans.

This test will not prove that the temperature is triggering the fan. Low and high speed fan is triggered by 2 different temp values and I don't recall what they are.

With the A/C on the low speed should be working. You can't hear it. You should just look.

But it sounds like it's working fine. It takes heat to get the high speed cranking.

///Rich

Thanks for the suggestions. I feel pretty sure it's working based on my experiences in traffic, but part of me has a need to be certain. Time to get eyes on the fan...

I'm not selling anything, but during my tool review, I found that the Schwaben scan tool can activate the different stages of the fan for your diagnostics. It isn't free, but if you needed an excuse for a really good scan tool... more toys!

https://www.northamericanmotoring.co...eo-review.html

Weird - I've seen the same thing recently on an 06 MCS with Chrono as well. Temp guage goes to 12:00 position (200-ish degrees?). Is that normal?

I believe that is normal. That is what my car (also Chrono) did prior to the fan and coolant work and what it does after the work.

That makes me feel a little better. :) Thanks for the info.