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Can someone confirm it is normal for both fans (thermo and aircon) to come on when engine reaches temp. Im sure only the thermo fan came on before my new ECU and tune.

Thanks

The second fan generally only came on when the air con was on. There were a few work arounds to make both fans come on without the aircon being on.

It's not a bad thing to have them both coming on.

No, not normal.

But also not a problem, quite a few people intentionally re-wire so both fans come on.


I'm guessing the old ECU must have sent out a separate signal to each fan/relay, where the new one just says "FANS ON"
As long as they're both working, and working at the right time, it's actually beneficial.

Yeh, I thought only one came on before as I have an extra switch that was rigged up to the aircon fan so I could have that running all the time (without A/C on) while on the track.
So now they both come on, which as you say is not a bad thing, my switch now seems to be turning on the other fan for some reason (thermo), so maybe for track days I will keep that turned on all the time for when the thermo fan isnt running, as Ive had a bit of trouble with temps on ot track days.
Thanks again for yur help guys, appreciate