A/C cooling fan and Radiator fan

I have two fans on radiator.One is for A/C,and other for Radiator cooling.I am under the assumption,(the mother of all f-ups),that both run separately or do they run as a team in the warmer weather?
I did notice the A/C motor the smaller of the two wobbles like the shaft is bent.Is there an aftermarket fan motor or can I purchase one from an autoparts store? And how do I know the fan motor for radiator works.I don't have any way of checking other than the temp gauge which goes to 190 and not any higher.
I have another question as well and it is about the size of a battery.I have a early 99 Jetta 1.9 TDI turbo and the CCA says 730? Can I go with same size battery with a higher CCA? If so,it will not hurt anything will it? Your answers help me out for a person with limited pocket money and just starting out with diesel cars
Ron

They run as a team! There is no difference (one is not for AC and the other for the Radiator)!

Turn on the AC, and both fans should run on low speed! If the coolant gets above a pre-set temp, both fans will kick-on up to a higher speed (with AC on or off)

If one fan is not working, it is either totally shot or the brushes inside are hanging due to road debris.

Battery size makes no difference, other than one too small may not start the car in during the cold winter months.

Check out the Vendors who support the TDIclub for fans!

We purchased a $ 40 "universal fan" at Advance auto, took it apart and put fan motor in our $ 319 Yamaha Rhino fan assembly. You may be able to do the same. I have not priced VW fan motors, but I'd guess they're more than $ 40