Pete Lech

Actually, the fans don't cut in until the oil temps are hotter than I would like to see.

In an autocross, you can cool down your oil temps between laps so you aren't starting off with the oil already hot. With higher temperatures, the engine management system will retard the timing, reducing power.

Randall G.

One more thought on my previous post. I think the hammer identifies a failed resistor indirectly. If the fan can't be operated in slow-speed with the hammer, an error is returned, and the shop manual specifies the jumper test. If I recall correctly (still no shop manual access).

swftiii

TCR - take a look at this for an explanation as to when the oil cooler fan is actually triggered.

The short reason is exactly what Pete mentioned, the factory settings don't turn the fan on until the oil is already too high and only on the slow fan setting. With the override switch, you can run it the moment you run into some traffic and it looks like you'll be sitting for a while, etc. With the switch not turned on, the factory settings and operation will work fine.

Another good reason is that it is fun to tinker with the car and do these kinds of things.

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