Cooling fan issues.

[Raven9]

15 non pp. both fans come on when started, turn on max ac, compressor kicks on, passenger fan dies off, drivers kicks in high. its causing my temps to break 200 and higher in town.
Relays and fuses all good
Unplugged temp sensor, no change, drivers fan stays engaged. What’s driving me mad is the pass will come on at start up, as soon as ac kicks on it dies off.
I’m thinking module, but can’t seem to find much on 6th gen stuff on my research here.
Any thoughts are appreciated. Thanks .

 

[Shadow351]

Don't know if you still need info on this but JIC.
Newest diagram I have is a 2013 so hopefully it's the same for a 2015. Motor 1 seems to be the Passenger side fan.
When in low, both fans are connected in series, so that deems Fuses F29, F31, & F70 as well as the NO contacts on the 'LFC' relay and the NC contacts on the 'HFC #2' relay all good.
When the 'HFC' relays kick in, each fan is then connected to its own fuse. Since Motor 2 is the one that works on high, that would indicate that F30 is good (so indeed that would indicate all related fuses are good). I'd check ground G101 next. How did you determine the relays were good? This looks like it could also be caused by a bad connection on the NO (pin 5) contacts/pin of the "Engine Cooling Fan Relay HFC #2"

I don't like that the naming in the BJB diagram doesn't match the schematics but I suspect the "Engine Cooling Fan Relay" is 'LFC' and "Engine Cooling Fan Relay #1" & "Engine Cooling Fan Relay #2" are 'HFC #1' & 'HFC #2' respectively.

 

[Raven9]

That’s awesome! Thanks, makes it a lot easier to track down now.