Funny thing, that is what I have done.
I have wired a switch & multimeter into the car in parallel with the radiator fan switch.
I wasn't sure my fan was coming on, so I wired a switch in parallel with the radiator switch into the car, together with a multimeter, so I could manually switch the fan on if necessary & also check when the fan was switched on by the radiator switch.
On a 20 mile journey the radiator fan never came on, not once.
When I was stationary for a period, the fan came on very occasionally for 10, 15, 20 sec.
That didn't seem right to me.
I guess as long as car is moving there is enough airflow to cool the radiator & system & the fan generally only kicks in occasionally when stationary.
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