At what temperature will the auxiliary fan on a 2001 X5 3.0i come on, if there is no mechanical fan, the replacement aftermarket electric puller fan is unplugged, and the HVAC is switched-off? I'm assuming that the DME has a specific temperature programmed. Or not?

I'm going to be using carb cleaner to test for vacuum leaks, and I'm wondering if the auxiliary fan can be trusted to keep the engine from overheating if I take too long a time underhood.

And I'll have some cardboard blocking the air blast from the aux fan, placed between radiator and engine, if the aux fan might come on too early, giving me added time to spray the hoses.

Meanwhile, I'll have a phone with Torque Pro app displaying coolant temperature, engine revs, and fuel trims in hand while spraying the lines, but am wondering how much leeway/safety margin I'll have if I get distracted.

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01 BMW X5 E53,3.0i-5L40E, 7/13/01
topas-blau,Leder-grau,"resto-project car"

Here:
14 Lexus ES350,3.5L-U660E
09 HHR Panel,2.2L-4T45E
04 Chevy 2500HD,6.0L-4L80E
98 GMC Sierra 1500,5.7L-4L60E

Gone:
66 Chevelle Malibu 2dr ht.,327>441c.i.-TH350>PGlide/transbrake
08 Cobalt Coupe,2.2L-4T45E
69 & 75 C10s,350c.i.-TH350
86 S10,2.8L-700R4
73 Volvo 142,2.0L-MT4
72 & 73 VW SuperBeetles,1.6l-MT4
64 VW,1.2l-MT4
67 Dodge Monaco 500 2dr ht.,383c.i.-A727
56 Chevy 210 4dr,265c.i.-PGlide