Can I swap relays with another R1-R2 to test if the low speed fan not working when ac is on.Not sure if AC is even coming on when switched, which fuses should I check.
2003 S

 

Just open the bonnet, start the car, turn the A/C on and check two fans.

First, the one for the PS pump should come on ( use a flash light to see if it spins) and second, the engine cooling fan will come on about 1 min later....that one your should be able to see and hear.