Yes

Look at the schematic.

If you use that low fan feed at the resistor [ single wire] for the coil of a seperate relay, with a ground for the other side of relay coil , when you toggle your cabin sw you have for the a/c pressure sw, the coil will pull in the extra relay's contactor set ..so, on the new relay , you just grab a good heavy 12v from Bat+ someplace , stick a 30A fuse in the line , and bring it to the relay contact terminal... the other side of the relay contact goes to the 2 wire side of the resistor..that gets you high fan instead of low when the a/c high pressure sw closes for a/c operation.. or when you use the cabin sw you already have hooked to the pressure sw at drier. That takes the R15 out of the circuit... notice low fan uses 2.5 wire and high uses 4.0 gauge ...if they both used the heavier wiring, you would only have to change the fuse at the low relay they use and do some terminal changes. @ R15......but guys that do that have had trouble with that 2.5 wire burning up...
You can see that the weak link in the low fan circuit is that 2.5 Bk wire running from the relay to the R15...the Input wire to that low fan relay is heavy enough, so some guys dig in there and change that 2.5 to a 4 or run another 2/5 along side and then change the low circuit fuse from 15 to a 30. Then you can just jumper R15 with a solid heavy wire, or move the single wire over to the R15 output side [ 2 wire side]
I like seperate relay cuz you can up the load capacity of the relay contacts.
Notice the high fan relay has dual contacts to share the higher load of high fan draw.
On the blu sensor, a 1500ohm will work, but you can use a variable to get that anywhere you want it and then just measure where you had it set for ohms an then install a value that matches.

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Guys do both these mods in real hot climates to help the a/c output and get a lower coolant temped sensed high fan protection.
The advantage to my set-up is you can get High Fan anytime you deem it needed..you are the sensor and you can over-ride the system at will...but at the same time, the stock set-up still will kick in by itself..
I know a guy I did this for and the idiot would toggle the high fan anytime he pulled into a place with other motorheads just to watch them look when the noise from the fans came on.....unreal

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A Dalton