Jay Wells

On a 2001 Tracker should the AC condenser fan run anytime the AC is on or does it only run when it reaches high temp?

oilcanhenry

As far as I know the fans will operate to keep your temps in the normal range regardless of the A/C, but of course they or one will or should operate when it's hot outside
and you have the A/C on.

L84sky

The short answer is yes, the condenser fan runs anytime the A/C is ON. The detailed theory of operation is shown below.
Note that the condenser fan can be switched ON by the PCM --- even if the A/C is OFF --- if an engine overheat is detected.

L84sky

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This is what my Tracker gauge looks like at normal operating temperature. According to the theory of operation the
needle starts going into the red at 230°F.




As an experiment I used the recording function of my Tech2 scanner to capture and graph the Engine Coolant Temperature (ECT) over time. When the recording
started the engine was already at 109°. After 3 minutes of driving the engine temp reached 195° and leveled off. The rest of this rant is about how the engine
holds the temperature rock steady at 195°.

The Suzuki engineers selected cooling components (radiator, fan etc.) so that the engine would not exceed 195° under the worst possible driving conditions
(imagine pulling a trailer up a 45° incline in Death Valley in the middle of summer at noon). But with that much cooling capacity available the engine would never
reach its optimum operating temperature under normal conditions. So the engineers installed a regulator. We call it a thermostat. Here's how it works. The
radiator and fan are trying to drive the engine temp down to say 120°. The thermostat says that's too cold and shuts off coolant to the engine. Without coolant
the engine temp rises. When it rises to 195° the thermostat opens back up and allows coolant back into the engine. Now the engine cools down again and the
cycle repeats. This back-and-forth between the heating and cooling forces takes place in such small increments they appear to be in equilibrium. That's why
the temperature graph levels out at 195°.

I called this a rant because of the amount of misinformation there is circulating on the internet. I just watched a "mechanic" on YouTube explain that once a
car warms up the thermostat doesn't do anything. That is absolute rubbish. The thermostat regulates the temperature while you drive. Other "experts" testified
that their car's overheating problem went away when they removed the thermostat. Sure it did but they just swapped one problem for another. Instead of running
too hot, now the engine is running too cold.

If someone ever tells you your Tracker will run better without a thermostat, just thank them and walk away.