I have a CLK and have a no Aux Fan condition. I swapped out all 5 relays and checked all of the fuses but still the same problem. I have a feeling after reading all of this that it may need an A/C recharge.

If that doesn't work, I'll try the jumper test and then check the resistor. Anyone have an pic of what that night look like?

I love the "turn on the fans whenever I want" idea with a manual switch - A little scarred to try this as I see 2-3 connectors coming out of what I think is the receiver drier. Which one do I attached the two leads from the manual switch to?